Yulong D100 MKII
 

 
 
A few years back I did a fairly extensive evaluation of the Yulong D100. It was my first experience with the brand and I was exceedingly impressed with its performance – so much so that I’ve tried almost all the Yulong products since then. Each has been impressive for its cost: The U100 is a nice compact USB DAC for a low price. The A100 amp complements the D100 nicely and offers extreme clarity and focus; I can’t believe it has not become more popular. And the new Sabre D18/A18 flagship combo is quickly becoming one of my favorite setups – I just can’t stop listening to it. Yet the D100 remains Yulong’s “bread and butter” product. It’s cheap enough to not be too far out of reach for people new to the hobby. And it sounds good enough to be used in a very high quality system. I like the fact that it grows with you – start with using it as an all in one DAC/amp. Later add a nice external headphone amp. Want to go balanced? The D100 has XLR outs. Of all the many items I’ve reviewed over the past few years, the D100 may be the one I’ve recommended to the most people.
 
When something is that good, how does the designer possibly improve it without raising the price by a significant margin? And does the D100 even need to be improved? From where I’m sitting it still looks like one of the top dogs in the sub-$500 category. Realistically Yulong didn’t really need to do anything with it. But they decided to go about it in a way that would offer a modest improvement without raising the price – incremental tweaking to the design based on several years of feedback from numerous customers. If you know where to focus, you need only to change a few things rather than rework the whole design.
 
Worth noting is the fact that Yulong now has an official North American distributor – Calgary based Grant Fidelity has an extensive track record for customer service, and offers full warranty and after sales support. They even give a 30-day in home trial period. That takes away the uncertainty of ordering from an overseas distributor.  
 

 

 
DESIGN
First up, if you haven’t read my original review of the D100, I suggest you take time to do so now. The general description of the MKII is the same and I don’t intend to cover all the same material - I’d rather focus on the specific changes to the hardware and the resulting difference in sound.
 
I admit that when I first became aware of the MKII, I was under the impression that it had only very minor changes. Specifically, I knew that the original had some random compatibility issues with the USB circuit: it just didn’t get along with certain computers. So I knew that had been redone. I also heard that the headphone amp section received minor changes to achieve a slightly warmer sound, due to some complaints that the original lacked enough body. So I really wasn’t expecting much of a difference at all. But I had to find out for myself.
 
As it turns out, there are some fairly significant changes that I was not aware of. Through the always helpful Rachel at Grant Fidelity I was able to conduct an interview with Yulong himself, the man behind the D100. Once again I’m grateful for her assistance since my Chinese is a bit lacking.
 
Q)  Can you describe the changes that make the headphone amp sound a little warmer than the original model? I don’t see any changes to the circuit itself.
 
A)  The original circuit design of D100 is very mature in our own opinion. There is no real need for modification of the design. The MKII version changes are mostly on sound tweaking through adjustment of circuit parameters. We have been collecting customer feedback on sound since we started selling D100 years ago and D100MKII is the result of delivering a sound that matched the feedback we collected. 
 
 
Q)  Is it still the case that the ASRC function resamples all data to a sample rate which you find to be optimal for the components in this design?
 
A)  D100 re-sampling rate was at 110kHz and this remains the same on D100MKII. We have chosen to use Japanese NDK high precision low noise crystal clock oscillator in the D100MKII so the final measurement is superior to the D100.
 
 
Q)  Did you notice any difference in jitter performance from the first version, when using a USB input? I know some people think the Tenor TE7022 receiver is inferior to the TI TAS1020B and I'd like to dispel that argument.
 
A)  Jitter performance is mostly affected by the ASRC circuit, not by the USB chip. As mentioned above, we used NDK clock oscillator in the MKII so the jitter measurement is superior to the original D100. As to which USB chip to use, TE7022 is for USB2.0 standard while TAS1020B is for USB1.0 standard. From real world applications, it has been confirmed by industry designers that T7022 is more reliable with better sound performance. Overall, D100MKII sound warmer, richer and offers better tonality balance / less fatiguing than the D100, plus more reliability through USB input with TE7022. We believe this will offer customers a better listening experience overall than the previous D100. 
 
 
Q)  Has there been any change in the function of the sound mode 1 and sound mode 2 options? Or does it still only deal with very high frequencies above 15kHz? 
 
A)  The D100MKII offers sound differentiation from 10kHz and up - this is better than the previous 15kHz benchmark. The sound difference between Mode 1 and Mode 2 is more distinct than before. 
 
 
So the D100MKII remains very similar to the original with the exception of the changes mentioned above. Hardware is still impressive - CS8416 DIR accepting toslink, coaxial, and AES/EBU inputs up to 24-bit/192kHz. AD1896 asynchronous sample rate converter. AD1955 DAC chip. Output stage with ADA4075 opamps for I/V conversion and OP275 for LPF and buffering. MCU controller. Linear power supply with large Plitron brand toroidal transformer. Headphone amplifier using OPA2134 opamp driving a discrete transistor diamond buffer. Though it was released several years ago the D100 is by no means out of date in terms of hardware. The changes are such that you won’t really spot anything different just by opening the case.
 
I’m certainly glad I asked about the “sound mode” update. I suspected there was some action in that department because there seemed to be a much more obvious different between sound mode 1 and sound mode 2. The original model made it very hard to discern and I always thought it was a missed opportunity – the idea was welcome but the implementation was off. Setting the -3dB point at 10kHz rather than 15kHz makes a much more significant impact in day to day listening. It still isn’t night and day between each mode but it can be useful in certain instances. I particularly like the results with the various Utrasone and Beyerdynamic models I tried – models which I find to have some excess energy in the highs that quickly becomes fatiguing. I realize that a similar result could be accomplished via EQ, but that isn’t a possibility unless a computer is involved in your playback chain, which usually isn’t the case in my house.
 

 
CHANGES
For the sake of clarity, allow me to summarize all the changes that I’m aware of between the original version and the MKII update.
 
Upgraded system clock
1)      Different USB receiver
2)      Upgraded system clock
3)      Minor circuit tweaks in the headphone amp section resulting in a warmer sound
4)      Lower threshold for “sound mode” options
5)      Updated Yulong Audio badge on front panel to match the Sabre models
 
It isn’t a vast amount of changes but as I’ll explain, it is enough to keep the D100 at the top of the sub-$500 DAC category.
 
EQUIPMENT
Associated gear used for this review:
 
Source: JF Digital HDM-03S music server, Squeezebox Touch modified with Enhanced Digital Output, Acer Aspire One laptop
 
Amps: Violectric V200, Analog Design Labs Svetlana 2, Yulong A100, Matrix Quattro Balanced, Yulong Sabre A18
 
Headphones: HiFiMAN HE400, Lawton LA7000, Heir 6.A, Audio Technica W1000x, UM Merlin, Lear LCM-2B, V-MODA M80, Earproof Atom
 
Power handled by a CablePro Revelation conditioner and CablePro Reverie AC cables. Interconnects include Signal Cable Analog Two RCA and Pailiccs Silver Net XLR. A variety of headphone cables were used including CablePro Earcandy (single ended) and Toxic Cables Hybrid (balanced) for HiFiMAN, with Beat Audio Cronus and Supreme Rose for custom IEMs.
 

 

 
LISTENING
After burning in the MKII for a week or so, I got right to it – direct comparisons to the original were the main goal on my agenda. Initially I did some listening on the new unit and from memory didn’t think it was much different than the original. I even said so in one of the forum threads. But when I put them head to head I was surprised to notice that the improvement was more significant than I had anticipated.
 
Starting with the headphone amp – I did see how the original could be a bit cold at times, especially with certain headphones. It was not my first choice with bass light models like the Audio Technica W1000, or even the more well rounded W1000x. Nor did I love it with my 600 ohm Beyer DT990s. The MKII is noticeably warmer in those instances. It won’t turn a Grado into a Denon. But in cases where a headphone is on the fence between “too cold” and “just right”, the MKII will tip it to the favorable side. When I heard the term “warmer” to describe the update I was concerned that it might lose some clarity in the process – clarity that people have come to enjoy from the original model. Thankfully that isn’t the case. If anything, the new model seems slightly smoother in the upper mids and highs. No less detailed, but smoother in the best possible sense of the word. This means some potentially grating recordings have more of a chance: I’m currently listening to Something to Write Home About by The Get Up Kids - certainly not the last word in audiophile quality recordings. The MKII presents it in a more tolerable and well rounded manner compared to the original. As we scale up to higher quality recordings the focus shifts from making things tolerable to extracting a bit more emotion and realism. Listening to Pancho Sanchez Conga Blue in 24/88.2 resolution, the MKII gives a more convincing sense of impact to the various percussion instruments on display. Maybe it stands out more to me as a drummer, but I do hear a decent improvement. And after listening to some of my favorite classical albums from 2L Records and Reference Recordings, I do hear a subtle improvement in refinement as well – the MKII handles complex pieces more gracefully, with improved air and separation being the main benefits. At the end of the day this amp is still not going to satisfy a hardcore headphone geek by replacing a high-end dedicated unit. But an extra helping of refinement and “maturity” certainly never hurt anyone, and for some folks this will be all the amp they ever need.
 
Moving on to the DAC section – the thought came to me that perhaps some of the improvement in the amp section was not due to changes to the amp at all, but rather a byproduct of the improved DAC which feeds it. I was hoping that I could discern a concrete difference when using the DAC only, in order to prove this theory correct. After listening back and forth with several nice amps including the Analog Design Labs Svetlana 2 SET amp, the Violectric V200, and Yulong’s own flagship Sabre A18 balanced amp, I was able to determine that the DAC itself is indeed subtly improved. Resolution seems turned up a small notch overall, while the top end becomes smoother. I would never call the original a “grainy” DAC but the MKII is smoother still. I believe this is what contributed to the less fatiguing sound in the amp section. Replacing the UMC oscillator (already a high quality clock) with a higher spec unit from NDK is very likely to blame for this improvement.
 
As with the original, minor differences between the single ended outputs and balanced outputs can be heard. Nailing down exactly what those differences are is tricky and I don’t think either one is necessarily “better”, but merely “different”. I did very much like the combo of D100 MKII and A18 amp. I know the A18 is part of the Sabre series and an ideal match for the D18 DAC, but the D100 also does a fine job. In fact I think some people may even prefer the MKII to the D18 depending on their preference for sound. The D18 is more spacious and live sounding while the MKII has a bit more of a “monitor-like” presentation, and will show more of the flaws in your bad recordings. I prefer the D18/A18 combo but for someone who already owns the MKII the A18 is a completely viable upgrade. Interestingly, I still prefer the original D100 when pairing with the A100 amp. I know the A100 was voiced with the original D100 in mind, and for some reason that combo just has synergy together. But for the other half dozen amps in my house right now the MKII is the better match.
 
Probably the biggest question on my mind was about the new USB implementation – like many around here I was under the impression that the Tenor TE7022 was lower on the scale of quality as compared to the TAS1020B from Texas Instruments. And perhaps in some situations it is. I do think it is easier to work with, a fact that contributes to its ubiquity among no-name eBay type DACs and other questionable designs. Yet from experience I have seen it perform transparently in highly resolving DACs like the Violectric V800. And again in the case of the MKII, the USB input sounds no different to me than the other options. My conclusion is that if paired with an excellent ASRC circuit the Tenor chip offers no disadvantage whatsoever. Factor in the increased reliability (you rarely hear of compatibility issues with the TE7022) and it seems like a good way to go. I do feel that around here we have a tendency to ascribe too much importance to each individual chip used in a design. I’m guilty of this myself. We need to keep in mind that we are not “listening” to any particular chip itself. Rather, what we hear is a complex network of components – the USB receiver sends an I2S signal to the DIR which then passes it along to the SRC, the out to the DAC, I/V conversion, low pass filter, then out through the headphone stage or rear outputs. The whole thing works as a system. We can speculate all day long about how much each individual part contributes to the end result, but if the sound is pleasing then there is no point in arguing. In the case of the MKII, I do think the result is as described by Yulong – smoother and less fatiguing, warmer, improved balance and tonality. That applies to all inputs including USB.
 
The downside is the lack of support for the 88.2kHz sample rate. This never used to bother me but I’ve steadily built up a decent selection of albums in the format so it does become a minor problem now. And of course I would have loved to see an asynchronous implementation added – but remember that we are talking about a refreshed design that does not cost any more than the original. What do you suppose the prices of components have done in the past few years since the original D100 was released: go up, or go down? Yet Yulong has managed to add some improvements while keeping the price identical. That’s impressive enough for me to forget about async USB at the moment. I do know that Yulong is at work on a dedicated USB to SPDIF converter. After trying various chipsets like XMOS, Via VT1731, and C-Media 6631, he went with the Tenor TE8802. So at some point it can be expected that the async USB design would work its way into higher end Yulong DACs. It just seems like a lot to ask from a sub-$500 all in one unit to include it.
 

 
CONCLUSIONS
The MKII update to the Yulong D100 qualifies as evolutionary rather than revolutionary. It addresses the few complaints I’ve heard about the original model, while maintaining the good aspects that many users have come to love. It even refines and expands on some of those. All while keeping the same price. Impressive, and enough to keep my strongest recommendation for a DAC in the $500 range.  
 
To put things into perspective for those who are unfamiliar with the D100 – this DAC is absolutely competitive with such highly regarded models as the Benchmark DAC 1, Lavry DA10, and Grace Design m902. It’s even superior in several ways, especially with the MKII update. And why shouldn’t it be? Many of the same hardware components are being used, in a well thought out design that is no less complex than the others. The only thing lacking here is the prestige of those well-known brand names. Worth noting is that the D100 sells for less than half the price of those models, which helps take away the sting of owning a “lesser brand”. I’ve owned all of those models and am confident about what I’m hearing. Just in case I doubted myself, there have been many other folks who posted similar impressions – a small sample can be found here http://www.head-fi.org/products/yulong-d100/reviews.    
 
The only thing left to address is about current owners of the original D100. Should they upgrade to the MKII or stick with what they have? That’s kind of like asking if someone should upgrade from an iPad 2 to the recently released “new” iPad. The upgrades are significant but not overwhelming, meaning the answer varies with each situation. If a user has compatibility issues with their USB connection, and a desire to use that input more often, the MKII will take care of that. Or if the D100 is used as an all in one unit, and the user finds the headphone out to be occasionally too thin, the MKII will address that as well. But for people who are pleased with the sound and functionality of their original D100, an upgrade to the MKII is probably not necessary. Yes, it does sound noticeably improved, but the difference is not massive. If an upgrade is desired it would make more sense to climb the Yulong ladder to the flagship Sabre D18 unit instead.

 
 
JF Digital HDM-03S
 



 
 
 
I’ve been using this device as my main source in my primary headphone rig for months. I’ve had the picture posted and a space reserved for review, yet I just haven’t had the time to get to it. Part of the problem is that I’ve been waiting until I had time to fully explore the network features, as well as mess with firmware updates. But with a newborn baby in the house and plenty of reviews on deck I feel like I just need to finish what I started. This will be my attempt at a more streamlined review.
 
So what exactly is the JF Digital HDM-03S? First off, the JF stands for Jing Feng, with the full name of the company being Shenzhen Jing Feng Digital Technology Co. As far as I can tell they do OEM work for others as well as design their own line of music servers. There is a full line of models ranging from the HDM-01D which is purely a transport only with no analog outputs, to the top of the line HDM-03 which has a host of features. The HDM-03S is sort of a budget version of the HDM-03 – it has most of the same features in a smaller form factor, and omits the output transformers and balanced XLR outputs. Aside from that it uses the same hardware and is really the bang for the buck model in the lineup. I chose it because while I appreciate a good analog section I knew I would mostly be pairing the unit with a higher end DAC. So the full HDM-03 was not necessary.
 
The device is basically a purpose built computer running a custom Linux install. It has no onboard storage but can act as USB Host for a hard drive through a pair of rear panel USB inputs. It can also pull audio over a network, either wired through Ethernet or WiFi (which requires a separate adapter). There are quite a few ways to use the thing – aside from playing FLAC or WAV files up to 24-bit/192kHz, it can also function as a stand-alone DAC via a pair of digital inputs. I use it as a transport with an external DAC by utilizing the coaxial SPDIF output, but it also has extremely capable RCA outputs and even a nice headphone out. Once connected to a network it can stream audio from a UPnP server as well as internet radio through its built in database. It can also stream directly from Foobar2000 over Ethernet. It can even record audio in 24/96 from the digital inputs and save the result as a WAV file. This really is a remarkably versatile device.
 

Click any picture to expand
 
The HDM-03S sells on TaoBao (a China based site similar to eBay) for 6200 Yuan which equates to about $1000 USD. I had a friend make the purchase for me and he was able to successfully communicate my request for the proper voltage, which is not user adjustable and must be set at the factory. I don’t know how often they sell to US customers as I’ve never heard of anyone else using one of these. The closest option I’ve seen for US buyers is from fellow Chinese hifi company Opera Consonance. They sell a unit similar to the HDM-01, called the D-Linear 7, through Grant Fidelity. I believe JF Digital provided the processing and enclosure, while Consonance handled the audio side of things. The interior looks more simplistic but it may still sound great. That device goes for $1250. It’s a bit more expensive than the JF models but it does come with a warranty and after sales support, and I believe they throw in a wireless USB adaptor as well. Consonance just released another model called the Reference 7. I can tell it is based on the same JF Digital platform but is probably reworked on the inside since it has a balanced tube output stage. Pricing will be somewhere north of $2500. 
 
DESIGN
Externally the device measures 12 inches wide, 14 inches deep, and about 4 inches tall. Weight is roughly 16 pounds. It looks like a slightly scaled down version of an Audio GD Reference 7 DAC since it shares a similar construction including the rounded corners. It’s heavy and seems built like a tank, ready to stand up to abuse. I notice design theme similarities with Classe gear, and I believe the new Ayon S3 streaming audio device uses a nearly identical enclosure. I speculate that Ayon is sourcing the same manufacturer for their enclosure as JF Digital and Audio GD because the similarities are just too close. 
 

 

 
The front panel is dominated by the 5 inch touch screen display. This is the main interface used to interact with the device. It uses a resistive panel rather than capacitive, which generally doesn’t hold it back much since all it requires is simple button pressing. Basic functions are accomplished by touch but for certain things the included remote control is required. A power button is the only physical button on the entire device.
 
The rear panel features RCA outs, coaxial digital out, coaxial and toslink digital in, Ethernet in, two USB ports, and an IEC power cable receptacle.
 
Internally, the design is very ambitious. Processing is handled by a 32-bit dual core 600MHz CPU with a dedicated DSP chip and 2GB of RAM. Because it is a dedicated audio device running a custom operating system instead of a multi-purpose PC or Mac, those specs are more than plenty. A fairly large portion of real estate is dedicated to the power supply section. It’s a linear design utilizing dual shielded toroidal transformers; one for digital with multi-stage post regulation, and the other for analog with a class A high speed active parallel servo design. A Wolfson WM8805 digital receiver handles signals from the digital inputs while the internal playback is sent straight to the DAC section in I2S form. The D/A conversion is handled by a pair of Wolfson WM8741 chips in dual mono configuration. From there the signal is sent out to the output stage built around quad OPA627 opamps and dual AD797 opamps. The DAC chips are supported by a custom made 1ppm precision system clock. Elna and Nover capacitors are used throughout. The headphone stage pulls the signal from the output stage and utilizes a TI TPA6120A2 for amplification. Volume control is accomplished in the digital domain and applies to both the RCA out and the headphone section. As with many designs using the Wolfson WM874x chips, the user has access to 5 digital filter settings, as well as a digital de-emphasis which can be turned on or off. That means plenty of ways to tweak the sound to your liking.
 

 
 

 

 

 

 

Power supply is robust
 

Headphone stage
 

From right to left: WM8805, dual WM8741, quad OPA627, 
dual AD797, TPA6120A2
 

Main processing section, complete with mystery chips
that have their markings removed
 
USE
The HDM-03S can play nearly any type of file you can think of. FLAC, WAV, AAC, MP3, WMA, ALAC, APE, and probably more that I can’t think of. The front panel says it handles 24/192 streams but I’ve successfully played  up to 24-bit/352.8kHz tracks as well. I assume there is some internal downsampling involved there since the Wolfson WM8741 chips top out at 192kHz. But it’s nice to know that whatever file I may throw at it, the HDM-03S will handle it well. It even supports CUE which can be troublesome to other devices.
 
Operation is best expressed in pictures. So I took plenty of those. As you can see, the main screen lists the song title including the extension (.FLAC, .WAV, etc). It lists the sample rate, time played or time remaining, and has all the basic transport features as buttons for touch operation. Volume level is displayed but it must be adjusted via remote control. After a short amount of time without activity, the display switches to a mostly black screen with just the title scrolling across. In later firmware versions album art is enabled but I didn’t like the way it worked. It seems the device would show any artwork in the folder being played, no matter the size. It took a while to redraw larger files, cut off space for title text, and generally didn’t add much to the experience. I do fine without it.
 
General navigation is a bit different than most audio streamers like this. Instead of selecting by metadata like artist, album, or genre, it simply displays a list of folders. So basically it goes back to a drag and drop style of arranging music on an external hard drive. It seems surprisingly effective though once the number of folders becomes high enough, navigation gets harder. You find yourself scrolling through quite a few before arriving at the one you want. I’ve come to love it though – it reminds me of browsing through a physical media collection. I might set out to find a certain jazz album, but prior to finding it I spot something else I want to try and end up listening to classic rock instead. The device does support the PlugPlayer app for iOS devices, so proper navigation is likely easier to do that way. Which brings me to my big issue.
 
I haven’t been able to get the device online yet. I tried three different USB WiFi adaptors. One ended up being defective all around but the other two do work on my various computers – but the HDM-03S doesn’t recognize them or even seem to give them power. I haven’t been able to figure it out. I could lug it into the other room and use an Ethernet cable but I just haven’t had the motivation yet. Without network connectivity, the device is still very useful for me, but I do need to figure it out one of these days.
 

 

 

 

Unfortunately my unit shows all incoming data as 44.1kHz
even when they are higher 
 

First find your album
 

Then pick a song
 

Song plays
 

Screen eventually goes to this mode
 

Handles most files types: MP3
 

FLAC from standard Redbook format
 

48kHz
 

88.2kHz
 

96kHz
 

176.4kHz
 

192kHz
 

Even 352.8kHz (which is quite rare to find)
 
LISTENING
I’ll cut right to the chase – this is a top class transport, a very good DAC, and a reasonably good headphone amp.
 
As a transport, it does exactly what I hoped it would, which is sound better than anything else I’ve heard. I’ve had some good to excellent transports around the house and done direct comparisons with many of them - Theta Miles, Lexicon RT20, Squeezebox Touch, NAD C446, Pioneer N50, Marantz SA-1 with extensive Audiomod upgrades, Classe CDP10, Rega Saturn, Esoteric SA-10, McIntosh MCD205, modified Sim Audio Moon CD-1… and I’m sure some others that I’m forgetting. The majority of these devices are highly regarded, with many priced in the multi-thousand dollar range. The Marantz SA-1 was $7500 when new and has another $7K worth of upgrades on it. Yet none of these could quite do what the HDM-03S can in terms of feeding a top quality, pure, low jitter signal to an external DAC. I really do think this device may have maximized what is possible from a standard SPDIF connection. Perhaps some megabuck $30K transport can do a better job but I’m unlikely to ever own such a device. The only competition I can see is one that doesn’t play by the rules of an SPDIF connection – I’m referring of course to asynchronous USB transfer. I believe the potential is higher for a well done async solution compared to even the best SPDIF signal. The hot ticket right now happens to be the $300 Squeezebox Touch with a custom add-on enabling a USB 2.0 output. This can pass 24/192 data asynchronously to compatible DACs with stunning results. I need to do more comparisons to see how much improvement that brings…. for now I can just say that no other SPDIF transport I’ve heard can touch the HDM-03S (in my experience).
 
So what differences do a great transport make compared to a merely good transport? The answer really depends on your DAC. Some DACs are happy with any reasonably good signal, and don’t seem to scale much higher. At that point there is no use in spending more money chasing a better transport. My Yulong D100 is one of those types – I don’t feel it sounds any better being fed by the HDM-03S compared to using a reasonably good transport like the Pioneer N50, Theta Miles, or just the stock SPDIF output of the Squeezebox Touch. So in that case there is not much benefit. But in DACs where it does seem to be more significant, you can expect things like tighter focus, a better defined soundstage, superior imaging, a more natural presentation…. All those “squishy” audiophile type definitions that can be difficult to describe or comprehend. Readers familiar with my style know that I’m not really the type to ascribe night and day differences in sound quality based purely on a transport. Yet it does make sense to me that a superior signal would be an easier “load” for the DAC to handle; even DACs with exceptional jitter reduction capabilities would be working with a more pristine signal right from the start, therefore guaranteeing the accuracy only hoped for by an ideal de-jitter process. So I don’t feel that I’m crossing the line into snake-oil nonsense here. As always, the reader is free to disagree with me.
 
When using the analog outputs, the HDM-03S sounds very good as well. It has a smooth analog feel to it that rivals many of the better stand-alone DACs I’ve heard. I compared it to the Rega DAC recently and to my ears the two sounded nearly identical. The Rega was ultimately superior by a small margin, having a more open top end with less veil, but it was a fairly close call. For those familiar with that unit, you’ll know what I mean when I say the balance of detail and musicality is very nicely done. Perhaps not the last word in ultra-analytical sonic precision but very involving and rhythmically correct. There’s a slight warmth over the presentation and it tends to make all music sound as good as possible. This is probably not the DAC you would use in a mastering session because it would tend to hide flaws in your mix. But for someone merely concerned with listening, it is a very nice sound.
 
As I mentioned the Rega DAC sounded nearly identical with the HDM-03S. I also hear a strong similarity to the Yulong Audio flagship Sabre D18 unit. That machine is the better DAC overall, taking the same recipe a bit farther to maturity. So ultimately the HDM-03S is not quite on par with my reference units like the Anedio D2 or Violectric V800. But those are dedicated DACs costing more than the HDM-03S, and they don’t have nearly as much functionality. If I had to rely solely on the JF Digital machine as my only DAC I would certainly be able to get by happily. I would rank it close to my Yulong D100 MKI or Matrix Quattro DAC in terms of overall ability, just trailing the D100 MKII. I’d also rate it slightly higher than the Pioneer N50 I recently reviewed (and enjoyed).
 
The integrated headphone amplifier is probably the weakest link of the whole device. Not that it is bad – on the contrary, it is generally pleasing with a warm smooth tone reminiscent of the RCA output. It has good performance overall and most people would probably be more than satisfied with it. As a bit of a headphone snob, I have many other dedicated amps to choose from, so I usually prefer one of my reference units instead. Comparing the headphone out to a quality budget standalone amp like the Matrix M-Stage or the Yulong A100, the built in amp is a bit hazy and indistinct, but does have very nice tonality and good low frequency control. Resolution is fair and imaging is clear enough to be convincing. I guess what I’m trying to say is that the amp is very respectable but doesn’t stand out as much as the RCA or digital outputs.
 

System takes just over 1 minute to cold boot
 

Progress bar lets you know how close you are
 
SUNDRY COMMENTS
A downside to the whole experience is the lack of after sales support. It’s not just the language barrier either – I get the impression from the manufacturer website that they aren’t as focused on individual sales as they are on finding OEM partnerships. For example, there are several firmware updates, but there is very little info as to the changes each one brings. Each time I’ve updated I’ve had a nervous feeling like I may be about to ruin the machine. There is also the matter of finding a matching WiFi adapter which has been mildly frustrating. Most companies would have a list of recommended adapters, or a forum where fellow users can post their results, or something to help the situation. Not so in this case. I'm also scared that I may somehow damage the remote, which would be a big deal. Many functions are only accessible with the remote. I'd have to contact the manufacturer and hope I could get a new one. I should hurry up and program my Harmony remote to duplicate this remote, just in case. 
 
There also appears to be a recent upgrade to the main processing module. The website doesn’t really say how one can update to the new version. It does list the specs, which happen to be the same as I already have in the HDM-03S (the newest of all the different models). So perhaps I already have the newest processor installed? To make matters worse, the new module is not quite a plug and play upgrade – each model has a different set of instructions for some hardware modification necessary to support the upgrade. It involves cutting traces and soldering. Since instructions exist to do this process for the HDM-03S, do I then logically conclude that I don’t have the updated processor after all? I don’t know. There are some very recent firmware updates that specifically state they only work with the upgrade. If I try them, will I brick my unit? I need to have someone translate for me to get answers to my questions. For now I’m keeping it as-is with the older but solid firmware.
 
CONCLUSION
The HDM-03S is a quirky device. With a little refinement and polish, it could easily be rebadged and sold as a much more expensive product. The sound quality is certainly there - this is quite simply the best SPDIF transport I have ever experienced. Yet those little quirks keep it from becoming something that has mass appeal for the general user. Lots of folks are accustomed to browsing by artist or genre and would have a difficult time with the folder-based navigation of this machine. But it works for me, and I feel like a bandit having only paid what I did for it.
 
By way of analogy: many people still prefer the experience of vinyl. It may have started with the sound quality but has become something more than that. They maintain expensive turntable rigs that have far less convenience compared to a music server or even a CD player. Yet they have become used to browsing their physical media, organizing it, cleaning it, selecting the particular album they wish to play. And in that way the aspect that is considered detrimental by many, becomes an enjoyable ritual by few. I’ve seen the HDM-03S referred to as a “digital turntable” according to Google Chrome translation. I think it’s an appropriate term. Scrolling through the directories, less than perfect as it may be, has become my ritual through which I have found many hours of enjoyment.
 
I don’t know if anyone else around here will ever own a JF Digital product. But for me this has become the foundation of my fairly substantial equipment collection. I’ve had some great network audio devices come and go through my system and have enjoyed them very much, but nothing has come close to replacing the HDM-03S. It isn’t the perfect device for everyone but it comes rather close for me. I can’t see it being displaced in my system anytime soon, and down the road I know I’ll have to spend an obscene amount of money to do any better.
 

 
 
 
 
 

 
 
 
Lear LCM-2B
 
 

(all pictures can be clicked to open full sized version)
 
Custom IEMs these days come in all shapes and sizes. With literally dozens of manufacturers out there, one can choose from any number of configurations – acrylic or silicone, full shell or canal-sized, armature or dynamic driver (or combination of the two), single driver all the way up to 8 drivers per side, under $200 to well over $1000. And that’s not even counting the appearance options which can be anything from a single solid or translucent color to detailed custom artwork or even exotic faceplates in wood, carbon fiber, brushed aluminum, glow in the dark… the possibilities seem endless. All these options are of course great news for the custom IEM purchaser, who now has more choices than ever before.
 
One difficult thing in all these options is the task of figuring out which model is the best fit for your needs. I’ve long wondered why industry pioneer Jerry Harvey chose to name his designs the way he did. In the beginning, there weren’t all that many options, but somehow Westone (arguably the “original” custom company) has evolved into using reasonable model names like ES1, ES2, ES5, etc. Mr. Harvey on the other hand seems to prefer an arbitrary numbering system and that practice has spread to a multitude of custom IEM firms. How is one to know the differences between the Ultimate Ears UE4 and UE5? Both are dual driver models but one costs $200 more than the other. How about the older UE7 and UE10 models? Both are 2-way triple driver designs with dual low frequency drivers and a single driver for highs. The UE10 was recently retired from the lineup but for years I wondered what the differences were (and if I had made the wrong choice when I ordered the UE10). Mr. Harvey moved on to found JH Audio and the confusion continued: JH7, JH10, and JH10X3 are all triple driver models priced within $100 of each other. If we dig into the descriptions it seems that the JH7 is for live performers, JH10 is extremely neutral, and the JH10X3 is…. well, “versatile and accurate” due to its 3-way crossover. Whatever that means. Are you starting to see the confusion here? About the only one that makes some sense to me is the JH16, because that’s the total number of drivers used in the design. 
 
Jerry Harvey is certainly not the only one using this tactic. Unique Melody has their Marvel, Mage, Merlin, Miracle series (and the Aero which somehow defies the naming convention). Other companies choose to simply use number of drivers as the model designator – see 1964 Ears with their 1964-T (for Triple) and 1964-Q (for Quad), or Heir Audio with the 3.A, 4.A, 6.A, and 8.A. This makes more sense to me, though it still necessitates investigation as to how each model is tuned.
 
I mention all this because I’ve found one company who has come up with a novel method of making this process easier - Lear. HERE is a link to their website which is thankfully done in clear English.The company originally launched in 2008 based out of mainland China, and ownership was eventually transferred to their Hong Kong distributor Forever Source Digital. Early products included universal IEMs and portable amps. As of last year the company has ventured into customs in a big way with a total of 9 different models, all distinct from one another. That’s the largest active line-up I can think of at the moment of any custom IEM company, which is very impressive for an initial offering.
 
The Lear method of categorizing customs is simple: first, choose how many drivers you want – one, two, or three, with higher numbers having better performance across the board. From there each choice breaks down into three different tuning categories: Bass, Crystal Clear, or Flat. So for example a single driver model can be had as the LCM-1F (short for Lear Custom Monitor I assume) for neutral performance, LCM-1B for bass emphasis, or LCM-1C for treble emphasis. This series remains for the two and three driver models. The method seems so simple yet so effective that I’m surprised nobody else has thought of it. 
 
It would be easy to start with three main designs and tune the sub-categories for flavor simply with acoustic dampers or crossover tricks. But I confirmed with Lear that each model is in fact a unique design with its own specific drivers, though I’m sure they also tune the whole design in every possible way (including dampers, crossovers, sound tube diameter, and even placement of the drivers within the shell, all of which makes a dramatic difference in overall sound). So an LCM-2F really is a completely different product than an LCM-2C. How refreshing. I’m not opposed to the way other companies choose their names, and I certainly do enjoy my other customs like the Earproof Atom or the Unique Melody Merlin. It’s just that I find the Lear naming method to be the most logical and descriptive (if perhaps not the most catchy). 
 
Pricing for the models is listed in HKD which as of today roughly translates to the following, including shipping to most any location on the planet:
 
Single driver models: $275
Dual driver models: $405
Triple driver models: $535
 
Those place Lear somewhere in the midrange of custom IEM houses in terms of pricing. 1964 Ears is cheaper and UM is roughly similar, while UE, Westone, and JH are the same for dual driver models but significantly more expensive for the triples.
 

 
DESIGN
For this review I chose the LCM-2B since it is apparently the most popular model in the entire lineup. I can see why this would be – dual driver models have traditionally hit the sweet spot for price/performance. In my experience, single driver armature designs just can’t deliver the full spectrum as well as I’d like, though some of them manage to sound reasonably good. But the dual driver segment is where things can really start sounding great, and the price is still fairly easy to stomach. The “bass-enhanced” version is kind of an obvious choice – all things being equal, many people tend to prefer warmth over neutrality or brightness. Not everyone of course, but I’d say a larger portion.
 
Lear uses acrylic only for their shells and offers a wide variety of colors. One can also choose artwork, from simple engraving to complex color printwork (which costs extra). I kept things pretty basic and went for translucent orange for the right ear, and translucent yellow for the left. Both sides have the Lear branding engraved on them. I’m exceedingly pleased with the way they turned out – but I’ll discuss that further in the next section. 
 
Internally, I can see that Lear uses a rather large armature driver for the lows, and a rather medium to small driver for the mids/highs. It appears that Lear has sanded off the model numbers on all four drivers so I can only speculate what they might be. The size appears roughly equal to the combo of Knowles Acoustics CI and ED drivers. That’s a winning combo that has been successfully used in several other designs, though of course Lear could be using any number of other variants from Knowles or Sonion. Both units are placed up close near the canal portion of the shell. Crossover components are attached to the rear of the larger driver. Each driver has an acoustic damper placed deep in the canal at the beginning of the sound tube. I think they are of the green 1500 ohm variety but it is hard to see well enough to be sure. Lear uses a dual bore design so each driver gets a separate sound tube that exits into the ear. 
 
So far this design doesn’t seem too different from numerous other dual driver customs I’ve encountered. But then comes something unique – the cable. Lear does use what seems to be the standard “Westone style” two pin connector that most companies use. But the cable itself is completely different from the usual braided model supplied with customs from Westone, 1964 Ears, JH Audio, UM, Heir, and most others. This cable starts with a 45 degree angle 1/8” plug and has a smooth finish throughout. The cinch and the plugs appear to have been hand made in small batches, and if I was shown this cable out of context I would assume it was an entry level aftermarket cable selling for maybe $50-100. It’s really a nice cable though there is one aspect which could be controversial: a complete lack of memory wire or any alternative method for securing the cable behind your ears. I didn’t have any issues once I learned to tighten the cinch under my chin, but I could see this being somewhat of an annoyance. Then again I know a few people who actively dislike the memory wire on typical cables so it could be considered a benefit for them. Lear advises that the cable is interchangeable with the standard Westone style cables.
 

 

 

 

 

 

 
The specs on the LCM-2B are worth mentioning: 
 
Frequency response: 20-16kHz
Impedance : 10 ohm @1000 Hz
Sensitivity : 116dB
 
The 116dB sensitivity is on the high side but not unheard of among custom IEMs. And Lear lists the same 20-16kHz response for all of their models, so I’m not sure if that part is significant. The main thing to notice here is the 10 ohm impedance rating at 1kHz. That seems like a low number – lower than my UM Merlin (12 ohms) which is the lowest I recall seeing. But anyone familiar with balanced armatures and especially multi-BA designs with crossover networks, know how wild their impedance curves can be. See a few example pics here:
 

 

 
So while the impedance at 1kHz is 10 ohms, it is likely to be significantly different at other frequencies. This is important when we consider that most portable devices have output impedances significantly higher than 1. I’ve seen measurements of various iPod Touch and Classic models and most are somewhere around 6 ohms. This means there is a very real chance of altered frequency response due to impedance interactions, at least around 1kHz where we know the damping factor is nowhere near high enough. To make matters worse, many of these portable devices have non-linear output impedances as well, rising significantly as they drop below 100Hz. What does all this mean in context of the Lear LCM-2B? Basically it means that portable devices aren’t generally the best sources to use when driving these customs. Using a dedicated amp is no guarantee either – many desktop and portable units have output Z of 5 or 10 ohms, which is just not low enough. Ideally you want something rated at less than 1 ohm. That applies to headphone amps across the board but the effects are more obvious with the LCM-2B than any other IEM I’ve experienced.
Interestingly, all of the other Lear models have stated impedances of 40+ ohms. So the LCM-2B may be the only model that has such stringent requirements.
 

 

 

 
 
 
BUILD QUALITY
There are a few companies out there who have set the benchmark for high quality customs in my experience. The first was Unique Melody with their flawless crystal clear shells. Then along came Heir Audio and matched UM while adding exotic goodies like hand carved wooden faceplates and colorful carbon fiber, as only a true artist could do. I know it is difficult to judge the entire company based off a single example, but if my set of LCMs are any indication, Lear deserves a spot right up there with the best. They have a very smooth polish similar to my UM Merlins and are completely free of any cloudiness or bubbles. Even the formation of the tips and sound bores is very precise. That’s not to say other companies don’t do a good job too – I’ve had good results with 1964 Ears, Westone, UE, JH Audio, and others. But Lear, UM, and Heir just seem to be on a higher level. As we’ve seen recently with UM, build quality yesterday is no guarantee of build quality today or tomorrow. It’s a constant struggle to maintain a reputation by delivering each new build just as good as the last. From what I read, UM has been having a bit of a lapse in quality lately, though I’m confident they can pick themselves back up to their former position. But based on my LCM-2B and the pictures on their website, Lear is right up there in quality. It certainly helps that my Lear customs fit extremely well without any need for adjustments. Clearly this is just as much due to my impressions as anything else, but the workmanship of the company plays a role as well. 
 

 

 

 
PACKAGE
 The package from Lear is about what I’d expect from a product like this, though the presentation is nicely done. The whole thing arrives in a medium sized tin storage container which looks as if it might contain a small loaf of delicious bread. Open the top and we find a foam insert with custom slots made for the IEMs themselves as well as the typical hardshell storage case. Inside that case we find the cable and a cleaning tool. There is also a user manual which is roughly similar to one of the variants that UM has used in the past. Again, none of this is outstanding in terms of functionality, but it does enhance the initial unboxing experience. The storage tin reminds me of the red faux leather box used by UM – novel but ultimately not very useful. At least Lear also included a regular case as well.
 

 

 

 

 
EQUIPMENT
Here is the equipment used in evaluating the Lear LCM-2B. You’ll notice that I used quite a lot of sources, including many DACs that have integrated headphone amps. I’ll explain later.
 
Source: JF Digital HDM-03S music server, Acer Aspire One laptop, Lexicon RT20 universal player
 
DAC: Anedio D2, Violectric V800, Audiotrak DR.DAC2 DX Muses Edition, Grant Fidelity TubeDAC-11, Yulong Sabre D18, Yulong D100 MKII, KAO Audio UD2C-HP
 
Amp: Violectric V200, Analog Design Labs Svetlana 2, Matrix M-Stage, Yulong A100
 
Portable: Sansa Fuze, Sansa Clip+, iPod 5G (all using Rockbox), QLS QA350, TCG Tbox, Audinst AMP-HP
 
Music used was a wide range of genres, mostly stored in FLAC format – everything from 16-bit/44.1kHz CD quality to 24/192 hi-res. Cables by Signal Cable, power conditioning by Furman, burn in done for almost a week straight prior to serious listening.
 
LISTENING
I’ll be honest – my first impression of the LCM-2B was not very positive. I plugged it in to my Rockboxed iPod 5G and the resulting sound was something I’d expect maybe from a $40 IEM using a dynamic driver… but not a $400 custom.  Bass was huge but loose and hazy, mids were totally sucked out, and highs were annoyingly glassy. Thankfully I had been somewhat prepared for this due to my awareness of the potential impedance issue. Next I tried my Sansa Clip+ which has a much more reasonable 1 ohm output impedance. This combination was far better – lows tightened up quite a bit, mids made their way forward into the mix, and highs smoothed out to some degree. But I was still hoping there was more improvement to be had. So far the LCM-2B was reminding me of my Westone AC2 – an interesting sound but far from my favorite choice. 
 
To cut right to the chase I moved straight to the top of the chain (in my experience) for IEM listening – JF Digital HDM-03S music server sending very low jitter signals to the new Anedio D2 DAC with integrated headphone amp (which is improved over the already stellar amp in the Anedio D1, my prior reference unit). The output impedance on the D2 is 0.035 ohms from 20-20kHz, thus no chance whatsoever of impedance related mismatches. If I was ever going to hear what the LCM-2B was capable of, this would be the way to do it. Finally I heard what I was hoping for: Big bass that remains well controlled, mids that sound natural and do not fatigue, and highs featuring a bit of sizzle without going too far overboard. One might say these are a nicely done implementation of the fun, “U shaped” sound signature - often attempted with varying degrees of success, but rarely done to my liking.  
 
Bass on the 2B is solid and certainly a focal point in the mix. Yet these are not quite the basshead customs I had thought they might be. Bass hits hard and has enough extra presence where classic rock, often recorded a bit on the thin side by todays standards, gets some extra oomph. At the same time bass heavy electronic music or hip-hop does not become overbearing (assuming it’s a decently recorded/mixed track, which a lot of hip-hop is not). Without having heard the other variants, I’d say that if the Bass model sounds like this, the Flat model should be extremely neutral and the Clear model would likely be too thin for my tastes. But that’s just speculation.
 
To give you an idea of the bass quantity here, the 2B has more bass than the 1964-T, LiveWires Trips, Earproof Atom, Westone ES3X, UE4pro, UE TF10, and Westone UM3X. It has less bass quantity than the Heir 8.A, UM Merlin, UE11pro, Westone AC2, or the Monster Turbine Coppers. Someone looking for an extreme basshead sound could possibly find them a bit short, and someone looking for a more neutral sound might conceivably find them to be a bit much. As I said – the U shape is hard to do right because everyone has their own thoughts on how much is enough. 
 
In terms of quality, the bass is quite good but not the best I’ve heard. At $400 I wouldn’t expect it to be so. Most of the time I was very pleased with the impact, texture, and overall realism it had. Once in a while I spotted a bit of looseness or lack of control. Nothing terrible, just enough to remind the listener that they aren’t using a flagship $1k custom IEM. I did appreciate how the lows stayed segmented away from the mids rather than creeping in and causing bloat. That’s a common mistake that bass heavy IEMs have and I’m glad Lear was able to avoid it so well.  
 
Mids on the 2B are interesting, as well as difficult to describe. There is a bit of distance in the presentation – vocalists sound pushed back on stage just a bit, like they are back among the ranks of their bandmates rather than out in front. It is not a dramatic effect and vocals are still very enjoyable. I played a few of my favorite vocal test albums, all very well done recordings available in hi-res format: The Persuasions Sing U2, Cantos de Agua Dulce by Marta Gomez, Ink by Livingston Taylor, Lay Me Down by Nancy Bryan… male and female voices alike sounded clear and natural, with good timbre and plenty of distinction in the mix. Yet they aren’t sticking out there in the same way that more forward headphones or IEMs make them sound. Another favorite of mine is the hi-res version of River: The Joni Letters, by Herbie Hancock with plenty of guest artists on board. The title track has Corinne Bailey Rae putting her own unique spin on this classic Joni Mitchell song. The 2B handles her voice well enough to where she is convincingly there in the room with me, and I can’t imagine anyone being disappointed with the presentation. As someone who regularly listens to customs and full sized headphones costing several times the price of the 2B, I am pleased with its abilities to render vocals.
 
Highs are as I mentioned prior: there is a bit of emphasis to bring out the sparkle and shimmer, but it remains subdued enough to not cause annoyance or fatigue. Just as it was with the bass, the emphasis is there but is not overwhelming. Bad recordings can show some sibilance though, which is unavoidable if we are to hear the full sparkle and airiness on good recordings. In this area the 2B reminds me somewhat of the LiveWires Trips and Westone ES3X. All of these sound wonderfully crisp and clear most of the time but can become shrill in certain instances. Blame it on the music or the wrong source equipment/amplification, but once a good match is achieved then it performs admirably. 
 
Overall detail retrieval is about what I’d call average for this class. Meaning it is not hair raising like the Earproof Atom but not as bland as the UE4pro. The focus is clearly on dynamics and musicality rather than background minutiae in the mix. Yet it will still show recording quality well enough – the original recording of the track “Sober Driver” by Dengue Fever, appearing on their album Venus On Earth, sounded clearly inferior to the redone version that shows up on In the Ley Lines, which was recorded and released as part of B&W’s Society of Sound series. 
 
If detail retrieval is just average for the class, soundstage and imaging are somewhat above the norm. Width is about what I would expect but there is some extra layering and depth which exceeds what I’ve heard from most dual driver models. Added to the lively bass and treble response, this makes for a very engaging, almost “live” presentation that is very enjoyable to listen to. 
 
COMPARISONS
It wouldn’t be fair to hold the LCM-2B to the standards of my more expensive customs like the UM Merlin or Heir 8.A, as those cost considerably more. So I chose a few models that go for roughly similar prices in order to even the odds. Keep in mind that this “entry-level” class of custom IEMs is extremely competitive – practically every brand has a very capable offering in this category. 
 
Earproof Atom
The dual driver Earproof Atom goes for roughly $525. It’s different in that it is only available in silicone and also uses a small form factor design that hides itself in the ear canal. In my review I described the Atom as sort of a junior version of the Ultimate Ears Reference Monitor. It is clear, neutral, and precise to a fault. The LCM-2B is very different sounding. If I had to call it a junior version of anything, I would choose the excellent 8.A flagship from Heir Audio. The 2B obviously doesn’t have the technical abilities as that masterpiece but it does have the same general feel of musicality. The 2B has significantly more bass than the Atom, while the Atom has the edge in tightness and exactitude. Mids on the 2B are more relaxed and spaced back in the mix. Highs are more pronounced with the 2B though not quite as extended. The Atom has a more “in your face” approach with an intimate soundstage presentation. The 2B is more spacious and distant. 
 
Despite being very different in sound, these two models are probably more alike than any of my other customs in one aspect – difficulty to drive. They both  sound disappointingly poor out of a standard portable device, and both come to life when paired with higher end source/amplification than one would expect for a dual driver IEM. It’s a somewhat unlikely practice for a $400-$500 custom to demand top notch source quality but that’s just the way it is with these two.
 
Westone AC2
The AC2 is actually fairly similar to the LCM-2B in most aspects. But the Westone model goes farther to the extreme. Bass is bigger, mids seem more recessed in relation to the rest of the sound, and highs are crispier. If the Lear offers a “U shaped” sound sig, it is a lower case u, while Westone is upper case with an exclamation point at the end. The Lear offering is certainly a more “safe” sound that I think would be appreciated by more people. I’m a bit torn myself. I much prefer the Lear upper mids and highs, as they are far less sibilant with many songs. But I do appreciate the way the AC2 goes all out with the bass, and it doesn’t lose its composure down there as the Lear is occasionally known to do. In the end I have to say that I would reach for the Lear more often than the Westone, though the latter does have moments of brilliance with certain recordings. Both of these are right around the same price so it’s quite an accomplishment for a new company to the custom game to beat one of the original players.
 
Aurisonics AS-1b
The AS-1b is a $600 custom. But if I close the adjustable bass port and ambient vent, the sealed result equates to the basic AS-1 model which goes for $400. So that’s a more fair comparison. I’m still getting a handle on the Aurisonics sound which is very mid-forward, owing to their stage monitor intentions. The massive 15mm dynamic driver is capable of cleaner and better low frequency reproduction than the armature driver used by Lear. In terms of specific tuning though the Lear has more forward bass, which is made to seem even more pronounced with the notched mids. The AS-1b has the opposite effect – bass is large and hits extremely deep but those forward mids steal some of the spotlight. The Lear model does seem to have more high frequency extension. Most of the time this was welcome, though certain music favored the smoother Aurisonics approach. Like the comparison above with the Earproof Atom, these are two excellent but extremely different sounds, and user preference would dictate which one is a better match for any given customer.
 
AMPING
I’m adding this special section which I don’t normally do, in order to help explain what works and what doesn’t. I tried the following equipment and found it to work well with the LCM-2B. Some of these are dedicated amps and others are all in one DAC/amp units or portable DAPs:
 
Grant Fidelity TubeDAC-11 
Yulong A100
Yulong D100 MKII
KAO Audio UD2C-HP
Anedio D1
Anedio D2
JF Digital HDM-03S music server (front panel headphone jack)
Violectric V200
Audiotrak DR.DAC2 DX Muses Edition
QLS QA350
 
The following devices did not sound great with the LCM-2B:
 
Analog Design Labs Svetlana 2
Matrix M-Stage
iPod 5G
iPad2
Audinst AMP-HP
TCG T-Box
Audinst HUD-mx1
 
In the middle: 
 
Sansa Fuze and Clip+
 
As you can see, most of the devices that match well tend to be on the expensive side while the poor matches are more likely budget gear. Most of this is simply a matter of output impedance – anything under 1 ohm should be suitable, and anything over 2 ohms is probably too high. My Svetlana tube amp is on the verge of sounding great, but the mids are slightly too thin, so I suspect it is right on the edge of being low enough when using the Low Z setting. Unfortunately many devices (DAPs, laptop and soundcard headphone jacks, plenty of dedicated headphone amps too) don’t specify their output impedance. It’s something you generally want on the low side anyway, but for this particular IEM it is absolutely essential.
 
CONCLUSION
The Lear LCM-2B is somewhat unremarkable in a way. It doesn’t have the best low frequency response I’ve ever heard. It doesn’t have the best extension up top, or the best overall detail levels, or the best anything really. Its strength lies in the fun, muscular sound signature, rich layering, and overall flattering presentation. Again, this is the type of thing that is easy to do wrong, to tip the balance slightly too far in either direction and thus ruin the result. For my tastes, the Lear LCM-2B hits a sweet spot which I don’t believe is matched by any of its numerous competitors. And for that it deserves praise despite not excelling in any one particular category.
 
The competition is very strong in this area. One can get a number of dual driver models from established competitors like Ultimate Ears, JH Audio, and Westone, and some triple driver models even dip down into this range. The LCM-2B is not one of those designs that absolutely blows the competition away. But I think we have entered a time where the market no longer allows for that to happen, or at least not as often as it once did. There are too many worthy contenders making great products, and only a small handful of them can climb to the top – where they will only remain for a short time before someone else comes along and knocks them down. Still, the LCM-2B performs very admirably. It is among the best dual driver customs I’ve encountered. It outperforms any universal IEM I can think of unless we move to insane prices like the AKG K3003. It expertly blends accuracy and musicality in a unique way that no other custom IEM I’ve heard short of the flagship Heir 8.A has managed to do. For that it earns an easy recommendation from me, and warrants some serious consideration. 
 
Reading this back, I realize that it ends up sounding a little negative. To put it in more positive terms – if I had to choose a $400 custom IEM, the LCM-2B would be among the very few choices at the top of my list. I’d choose it over the dual driver models I’ve heard from Westone, LiveWires, and Ultimate Ears, and would seriously consider it over some of the triple driver competition as well. That’s very impressive for a debut product. If you are looking for a fun, musical sound signature that tends to make most recordings sound great, and if you have the proper source with low output impedance, the LCM-2B is an excellent choice. 

 
 
 

 
A while back I was contacted by a representative from Korean based Gyrocom asking if I was interested in reviewing their DAC product. Gyrocom? I had never heard of them. Yet the device doesn’t carry the Gyrocom name at all, but rather is branded as Audiotrak. Now that’s a name I am somewhat familiar with: I’ve heard good things about the portable Audiotrak ImAmp as well as the Prodigy line of soundcards. Apparently there is a group of companies working together under the Audiotrak banner, including ESI which was a popular name in pro audio for a while. Here is a link explaining the situation.
 
The focus of this review is the Audiotrak DR. DAC2 DX Muses Edition. That name is a mouthful, so I’ll be calling it the DX from here on out. From what I can tell the DR. DAC2 DX has been around for a few years, gathering a decent amount of praise from places like Headfonia. What’s new on this version is the “Muses Edition” aspect. The DX features socketed opamps throughout, and the Muses Edition replaces all of them with the Muses 8820 bipolar input dual opamps from New Japan Radio Corporation. Apparently Gyrocom/Audiotrak felt that change resulted in such a significant gain over the stock configuration that they made a new release out of it. At the same time, the old price of roughly $375 has dropped to $329. I hear that the DX is a rather popular DAC in Japan but somehow failed to translate very well to the American market. Perhaps the Muses Edition can change that.
 
DESIGN
Even before the opamp upgrade, the DX is a fairly ambitious design for its size and price. Packed in a compact enclosure not much bigger than the Audinst HUD-mx-1, the DX shares many design cues with that device; similarities that made me wonder if the two companies were somehow tied together. They aren’t, as far as I can tell, but both are based in South Korea, so maybe the designs of their devices are indicative of the style trends in their home country. Whatever the case, the DX is similar to the Audinst but much more advanced, and priced accordingly higher.
 
The front panel is dominated by dual ¼” headphone jacks – left side having a gain of +8dB, right side having a gain of +20dB. There is a volume control which applies to headphone out and line out as well as a switch to choose which of those outputs will be active. A pair of switches allows selection of analog or digital input, and USB or SPDIF. Lastly we find tiny LED indicators: one for power that is always on, a row of them indicating the current incoming sample rate, and one labeled “Active Indicator”. That one seems to light up as sound comes through the device, but is fairly dim until you crank the volume over 50%. It seems to act sort of like a VU meter, pulsing brighter or dimmer along with the intensity of the music. I don’t really get the point of it but it certainly isn’t bad either.
 

 

 
Around the back we find a plethora of inputs and outputs: Line Out is for use with an external amp, and Line In allows headphone monitoring of analog sources. On the digital side we find coaxial and toslink inputs as well as USB. There is also a toslink output which acts as a pass-through if properly configured – like the Audinst mx-1, the DX pairs well with HTPC applications and allows surround sound signals coming in via USB to pass through to a home theater receiver. Lastly the rear panel has a port for the external power supply. Unlike the Audinst, external power is a requirement.
 

 

 
Internally the DX is packing some pretty high quality hardware. The DAC itself is a TI PCM1798. From there the device uses a fully differential output for I/V conversion consisting of 3 opamps, each a dual channel model. The original DX used a trio of the classic NE5532 opamps, but of course the Muses Edition swaps those in favor of the Muses 8820s. Line out originally used an OPA2134 while the headphone out was OPA2604, both of which are now 8820s as well. Note that the headphone out uses the opamp to drive a relatively complex (for such a small device) array of discrete transistors. Other parts are of good quality as well: WIMA condensers, SamYoung LXV series low-ESR electrolytic capacitors in the power supply, and Sanyo OSCON decoupling capacitors. Volume control is handled in the analog domain by an ALPS potentiometer. Here is the list of general specs from the Audiotrak website:
 

[size=7pt]Power supply

	[size=7pt]DC 15V / 1A~2A[/size]
[size=7pt]Dimensions / weight[/size]	[size=7pt]140(mm) x 111(mm) x 30(mm) / 440g[/size]
[size=7pt]Headphone Output[/size]	[size=7pt]Type[/size]  [size=7pt]Maximum Out Level[/size]  [size=7pt]Maximum Load Power[/size]  [size=7pt]THD+N[/size]  [size=7pt]Impedance[/size]	[size=7pt]1/4” Stereo phone jack[/size]  [size=7pt]Port 1 : +8dBV (6Vpp) / Port 2 : +20dBV (24Vpp)[/size]  [size=7pt]500mW[/size]  [size=7pt]0.0008% A-weighted (@ 100mW, 1kHz)[/size]  [size=7pt]0Ω (Load : 16 ~ 600)[/size]
[size=7pt]Line Input / Output[/size]	[size=7pt]Type[/size]  [size=7pt]Level[/size]  [size=7pt]Impedance[/size]	[size=7pt]Unbalanced RCA[/size]  [size=7pt]-10dBV Nominal (@-16dBFS) / +8dBV max[/size]  [size=7pt]15kΩ(Input) / 200Ω(Output)[/size]
[size=7pt]USB Audio[/size]	[size=7pt]Type[/size]	[size=7pt]Max 24bit / 96kHz, USB 1.1 / 2.0 Compatible[/size]
[size=7pt]OS Support[/size]	[size=7pt]Support Windows 7, Windows Vista, Windows XP, Mac OS-X Note: The Pass-through Digital output is available to Windows Vista(SP1) and Mac OS-X only.[/size]
[size=7pt]Digital Audio Input[/size]	[size=7pt]Type[/size]  [size=7pt]Format[/size]  [size=7pt]Sample rate Detection[/size]	[size=7pt]S/PDIF Optical on TOS-LINK 44.1~192kHz[/size]  [size=7pt]S/PDIF Coaxial on RCA 44.1~192kHz[/size]  [size=7pt]IEC-60958, S/PDIF Compatible[/size]  [size=7pt]44.1, 48.0, 88.2, 96.0, 176.4, 192.0 kHz (@ ±3%)[/size]
[size=7pt]Digital Audio Output[/size]	[size=7pt]Type[/size]  [size=7pt]Format[/size]  [size=7pt]Sample rate Detection[/size]	[size=7pt]S/PDIF Optical on TOS-LINK 44.1~96kHz[/size]  [size=7pt]IEC-60958, S/PDIF Compatible[/size]  [size=7pt]44.1, 48.0, 96.0 kHz[/size]
[size=7pt]D/A Converter[/size]	[size=7pt]Type[/size]  [size=7pt]Dynamic Range[/size]  [size=7pt]THD+N[/size]  [size=7pt]Frequency Response[/size]  [size=7pt]Gain Mismatch[/size]	[size=7pt]24bit, 192kHz, 8times Digital filter[/size]  [size=7pt]123dB (@ -60dBFS with A-Weighted)[/size]  [size=7pt]0.0005% (@ fs=44.1kHz, 0dB)[/size]  [size=7pt]0 ~ 21.7kHz, ±0.0002dB (@ fs=48kHz)[/size]  [size=7pt]0 ~ 43.5kHz, ±0.0002dB (@ fs=96kHz)[/size]  [size=7pt]0 ~ 87.0kHz, ±0.0002dB (@ fs=192kHz)[/size]  [size=7pt]±0.5%(channel to channel)[/size]
[size=7pt]OPAMP[/size]	[size=7pt]Operating Voltage[/size]	[size=7pt]24.0V(±12V),[/size]  [size=7pt]FDO : MUSES8820 x 3 (DIP, Socket Type)[/size]  [size=7pt]Line Out : MUSES8820 (DIP, Socket Type)[/size]  [size=7pt]Headphone : MUSES8820 (DIP, Socket Type)[/size]  [size=7pt]Line In : NJM4580 (SMD)[/size]
[size=7pt]Power Consumption[/size]	[size=7pt]About 4W~6W (5W / typ)[/size]

[/size]  
Note the 0 ohm output impedance on the headphone output – this amp section should be good to power even extremely low impedance IEMs without negative interactions. Due to lack of specifics, I inquired about the power output on the headphone jack. I was told that the DX is capable of the following:
 
500mW at 32 ohms
400 mW at 300 ohms
200 mW at 600 ohms
 
My contact advised that the setup was actually capable of more than 1W at 32 ohms but they felt that may be detrimental to user hearing and/or headphones. Apparently they don’t have experience with the latest planar headphones that can soak up juice well beyond a single Watt. This makes sense if we consider the time frame when the DX was originally released – Planar headphones were not popular at the time. But as I hardly anticipate anyone running an HE-6 straight from the DX, these specs are more than plenty for the majority of headphones on the market.
 
Since the USB receiver is the Tenor TE7022, the DX can handle signals up to 24-bit/96kHz with the exception of 24/88.2 material ( a limitation of the receiver rather than the DX itself). SPDIF inputs are routed through the AKM AK4117VF receiver which can handle up to 24/192. I don’t have anything capable of sending a signal higher than 24/96 over toslink, but I am able to confirm that 24/192 and 24/176.4 work perfectly over a coaxial digital connection.
 
The Muses 8820 itself is an interesting piece. The first time I heard of it was when Esoteric used it in their new D-07 DAC ($4800), a device which I was not particularly impressed with. For a while I recall seeing the 8820 for sale online at ridiculous prices as high as $80. Now I see Gyrocom themselves offering the 8820 on eBay for $9 each which is far more reasonable. Based on specs, the 8820 is not amazing, though it isn’t bad either. I’ve heard various DIY folks talk about how it is crucial to match this opamp with the proper circuit – that just dropping it into most designs will have deleterious effects. I have to assume that Gyrocom knew what they were doing when they chose this specific opamp to replace all three of their original choices. I will say that the Audinst AMP-HP portable amplifier uses the same 8820 in a socket – I’ve tried replacing it with numerous opamps from all the usual suspects, and so far none have sounded as good (in that particular application of course) as the 8820.
 

 

Tenor TE7022L USB receiver
 

TI PCM1798 DAC
 

AKM AK4117VF Digital Interface Receiver
 

Muses 8820s all over the place
 

Discrete transistors for headphone amp
 

ALPS pot
 
BUILD QUALITY
 
The DX is a well built little box. As I mentioned prior it shares aesthetic sensibilities with the Audinst mx1, and the same applies for build quality as well. Solid but not fancy, the DX has tight fit and finish as well as very well done graphics (which feature prominently along the top of the case). I appreciate that although the rear panel is hurting for real estate, they left just enough spacing for larger interconnects and digital cables to slide into place.
 
Aside from that pulsating LED which I mentioned above, everything works as expected: silent background, no static during volume control, and good channel balance at low volumes even with sensitive IEMs.
 
PACKAGE
 
The DX comes in retail style packaging which reminds me of the box you’d expect from a nice soundcard. That makes sense because from what I hear the DX is commonly found in shops throughout Japan. Inside the box are all the basic accessories one would expect to find: power supply, user manual, USB cable, and a basic RCA interconnect. There’s nothing too impressive but it isn’t lacking either – I’ll simply call it “complete” and leave it at that.
 

 

 
EQUIPMENT
 
Here is the associated equipment I used to evaluate this device - I kept things relatively simple this time around.
 
SOURCE: Lexicon RT20 transport, Acer Aspire One laptop, JF Digital HDM-03S music server
 
AMPS: Violectric V200, Analog Design Labs Svetlana 2
 
HEADPHONES: Audio Technica W1000x, Lawton Audio LA7000, Heir Audio 8.A, Aurisonics AS-1b, HiFiMAN HE400, Sennheiser HD700 prototype
 
SPEAKERS: Serene Audio Talisman Active, Emotiva airmotiv 5
 
I let the unit burn in for about a week prior to listening. Cables used were from Signal Cable, power conditioning was sometimes provided by Furman (other times plugged straight into the wall). Music used includes a wide variety of genres in FLAC format or occasionally CD, from 16/44.1 to 24/192 and everything in between.
 
LISTENING
 
My first impression of the DX through the Serene Audio Talisman monitors was that it seemed fairly neutral, but with slight tilt towards the musical side rather than analytical. Details flowed freely but were not “in your face” like some devices. The bottom end was pleasing – clearly being limited by the small full range drivers of the Talismans rather than the capabilities of the DX. Mids had an inviting warmth while retaining a nice balance overall. In short, this was a good pairing. I decided to venture out and try different equipment in search of further strengths or weaknesses of the DX.
 
Next came the airmotiv 5 monitors from Emotiva. These active monitors feature a ribbon tweeter for extended airy highs and excellent detail. This tweeter showcased the nice extension on display from the DX – not shouty, bright, or overly hyped, this is what I’d call a natural sounding DAC without veering into “dark” territory. Being musical yet mostly neutral meant the DX/airmotiv combo was as comfortable with the 24/96 release of Kent Poon’s Audiophile Jazz Prologue III as it was with Superunknown by Soundgarden. Once again, a great match overall between DAC and speakers. Having the variable output was certainly appreciated when using powered monitors.
 
Moving away from the realm of active monitors, I figured I should give the headphone amp a good workout. This is HeadFi after all. My initial pairing was the prototype of the new Sennheiser HD700, which should be available as a final release one of these days (thanks again to Sennheiser for the preview – I miss it now that I’ve sent it back). This 150 ohm headphone is nowhere near as difficult to drive as its older sibling the HD800. It doesn’t require the delicacy or finesse in dealing with potential brightness issues. Yet the HD700 does have a trace of similarity in that aspect – it did not pair as well with my brighter amps, and generally sounded best on tubes or smooth solid state designs like the Violectric V200. Similarly, it benefited from having a neutral or just slightly warm sounding DAC in the chain. The DX made a good pairing – slightly warm and musical but not overly so, it brought out most of the quality that the HD700 has on tap. 100% of it? Of course not. The HD700 still responded favorably to a multi-thousand dollar setup. It just wasn’t as much of a requirement as it had been with the HD800. I certainly enjoyed the low frequency kick on the XRCD release of The Joker by Steve Miller Band with the HD700/DX combo way more than I ever have on the HD800 paired with any sub-$500 DAC/amp. I no longer own the HD800 so I can’t comment on how well those match with the DX – but that would be a rather unlikely pairing anyway.
 
Next I moved to the Audio Technica W1000x. This 42 ohm model can easily sound unimpressive or downright poor when paired with the wrong equipment. It definitely benefits from system synergy, perhaps more so than the majority of headphones out there. The DX did a respectable job here but I wouldn’t call it ideal. The slight warmth was fine most of the time but sometimes brought out too much of the mid-bass emphasis that the W1000x can have. And the ever so slightly forward mids worked with some music like Big John Patton’s Mosiac Select release. But in other cases such as Paper Airplane by Alison Krauss and Union Station, the mids felt a little overcooked. The general theme with this combo was that instrumental tracks did pretty well but vocals were just too forward to be pleasing.
 
I tried a few of my higher end custom IEMs and found that the DX was a great dance partner for them. A nice quiet background laid the foundation for a solid performance overall – I especially appreciated the left headphone jack having lower gain than the right, enabling me to have more usable range for volume adjustment. And the extremely low output impedance was also appreciated – even my Lear LCM-2B customs with their wacky 10 ohm impedance rating and 116dB sensitivity sounded excellent with no interactions in the frequency response. This really is a versatile little all in one unit.
 
Lastly, I tried out my latest full size acquisition, the HiFiMAN HE400 planar model. Despite being advertised as being easy to drive compared to the other models in the HiFiMAN lineup, this is still a relatively demanding headphone. The DX seems to have plenty of juice though – in terms of control and dynamics, it matches the Matrix M-stage dedicated amp when driving the HE400 (though the two amps each have their own character traits). I thought that the unit matched particularly well with overall sound of the HE400, which like the DX is all about musicality instead of hyper-detail. At just over $700 for the combo the HE400/DX pairing is an excellent way for someone to get a high quality headphone experience without spending excessive amounts of cash. 
 
COMPARISONS
 
Audinst HUD-mx1
The little Audinst has been a favorite in the sub-$200 category for several years now. It still has a soft spot in my heart because it was one of the first detailed reviews I ever did on HeadFi. And to this day it remains a solid performer. What the DX does is build on that foundation, giving a similar overall presentation yet improving it in most areas. Resolution seems higher, low frequency impact is weightier yet more controlled, and soundstage presentation is slightly more refined. There’s no single aspect where the DX blows away the mx1, yet cumulatively the DX belongs in a higher class. I’m currently using the original stock opamps in my Audinst but I’ve done quite a bit of rolling through the various options, and I can confidently say that none of them brought it close to the same level as the DX.
 
I know many people first got into good audio by using the Audinst with their computer as an entry level setup. By now, some of those people may be looking for an upgrade. The DX is an obvious choice since it keeps many of the same features and even the same aesthetic of the mx1 while adding more options and improving the sound. It’s kind of a “no brainer” upgrade unless the user wanted to try a completely different signature.  
 
Grant Fidelity TubeDAC-11
In my review of the TubeDAC-11, I called it the best performer in its class, so I obviously liked it better than the DX overall. Is that it then? End of story – buy the TubeDAC-11 over the DX and call it a day? Not quite. As I mentioned in that review, the DX has several benefits over the Grant Fidelity model. Things like USB to toslink conversion and Dolby Digital/DTS passthrough enable the DX to be useful in situations where the TubeDAC would not be. But more than that – the DX is way smaller than the TubeDAC. The DX is nearly half the size of the TubeDAC in length, width, or height. That means it can go places that the larger unit simply cannot go. Places like my cramped computer desk, which can barely fit the Serene Audio Talisman speakers but certainly not the Emotiva airmotiv 5s. When available space is at a minimum the DX is the best option I can think of – better than the Audinst, or the AMB gamma2, or anything else I’ve tried. It’s a case where size certainly does matter. And it doesn’t give up all that much in terms of overall sound quality – many people would have a hard time telling the two units apart.   
 
Matrix Cube
The Matrix Cube is a solid performer in the $300 price range. It goes a little farther than the DX in terms of musicality rather than detail. By itself I never felt the Cube to be lacking, but in direct comparison to the DX I find it somewhat veiled and overly thick. It retains a slight edge in soundstage size and accuracy and is still a fun listen. But overall it gets outclassed by the DX in both sound and functionality. Again, my Cube does not have socketed opamps, so the newer models may have more potential when swapped with better chips.  
 
CONCLUSION
 
The Audiotrak DR. DAC2 DX Muses Edition is impressive on multiple levels. First, the sheer number of features it packs into such a compact enclosure, all of which are done well. Second, the high quality of the audio output through both the line out and the headphone amp is very much above average. Third, the fact that it is comes very close to matching my top pick in this price category – despite the DX already being on the market for roughly 4 years, says a lot. The Muses opamp upgrades are clearly a good choice if they bring the device up to this level. And all this takes place while the price of the unit actually drops by nearly $50.
 
It would be easy to dismiss this little device as a toy. One might expect basic features such as 16-bit/48kHz USB input, a simple headphone section driven solely by an opamp, and not much else as far as options. Instead we get hi-res over USB, a fairly complex and powerful headphone amp using discrete transistors, USB to SPDIF conversion, surround sound passthrough, pre-amp functionality, and even an analog input. I’m surprised, impressed, and very pleased with this device, and I recommend looking into it if its feature set matches your needs.  

 
 

 
A few years back, I recall hearing praise for a little DAC from Grant Fidelity called the TubeDAC-09. It was a compact unit with a good amount of inputs, offering both tube and solid state outputs. It reminded me of the Maverick Audio TubeMagic D1, also a popular unit in its price range, and I believe the two models were somehow related. Fast forward several years later, and Grant Fidelity has a new model: the TubeDAC-11. Rather than building on the original, the 11 is a completely new design. The only thing it shares with the 09 is the basic form factor and the TubeDAC name.
 
This time around there should not be any other products showing up with a similar design but different name. The reason? Grant Fidelity contracted exclusively with Yulong Audio to design and build the TubeDAC-11. This product is exclusive to Grant Fidelity; there will not be a Yulong branded version sold overseas in different markets. And as a Yulong design, one can reasonably expect solid performance at a great price. That’s exactly what I anticipated as I waited patiently for my black TubeDAC-11 to arrive. At $350 this would not be the cheapest Yulong design currently available, or the most expensive. I had a suspicion that it would redefine what was possible in its price class. Read on to find out if that ended up being the case.
 

 

 
DESIGN
The TubeDAC-11 is an interesting mix in terms of design. It takes some elements of other Yulong equipment and combines them, while adding some unique aspects all its own. With regards to functionality this is by far the most versatile of all the Yulong gear.
 
The case is very similar to the Yulong A100 amp – just like the D100 DAC, but with the vented top plate for heat dispersion. The front panel is centered around two large knobs: one for volume control, the other for rotating through the various inputs. A ¼” headphone jack sits between the knobs. LED lights indicate power and digital signal lock. And that’s all there is – simple and effective.
 
The rear panel is a lot busier. Starting on the right side, we find the IEC power cable receptacle and the voltage switch that allows this device to be used all over the world. Next comes a bank of digital inputs. USB accepts up to 24-bit/96kHz signals, while toslink and coaxial SPDIF handle up to 24/192. Moving further to the left gets us two sets of analog inputs. These allow the TubeDAC to be used as a preamp or stand-alone headphone amp. The area on the far left side is for the three separate outputs. DAC Direct is a line level output which bypasses the pre-amp stage. This is supposedly best for connecting to an external pre or headphone amp. Next is the tube out, followed by the solid-state line out, both of which are controlled by the front panel volume knob. Obviously the one gets passed through the tube section and the other does not.
 
If you were keeping score, that’s a total of 5 inputs and 4 different outputs if you count the headphone jack (all of which are active simultaneously). That’s a lot of functionality from a relatively low cost device. Plenty of headphone amps advertise pre-amp capabilities, but this is one of the few that I’ve encountered which is actually versatile enough to be used in that role without any compromise.
 
Internally, the TubeDAC-11 bears resemblance to various Yulong designs. The power supply is a linear design with a relatively large toroidal transformer. The DAC section uses the flagship CS4398 24-bit/192kHz delta-sigma DAC from Cirrus Logic. The integrated headphone amp section is built around twin Analog Devices ADA4075-2 opamps driving a discrete transistor diamond buffer circuit. It is capable of delivering 110 mW into a 300 ohm load, and up to 600 mW into a 32 ohm load.
 
The USB input uses the ever-popular Tenor TE7022 receiver capable of handling 24/96 signals. SPDIF signals are routed through a Cirrus CS8416 digital audio interface receiver, which tops out at 24/192. Unfortunately the USB connection did not work with my iPad2 via the Camera Connection Kit – it gave the typical error message about drawing too much power. I believe this to be the case with all Tenor TE7022 based USB inputs.
 
Then we come to something never before seen in a Yulong product: a tube. The included tube is a Chinese 6N11 but can be swapped for 6922, ECC88, 6DJ8, 6H23n, and probably some others that I’m forgetting. The tube acts as a buffer when Tube Out is used, and this device could even be used as a stand alone tube buffer if the owner so desired. Volume control for Tube Out and Line Out adjusts output from zero to 6 Vrms. This allows for even more options, since different external amps will have different expectations for voltage levels on their inputs. With all the options on offer, it’s difficult to think of a scenario where the TubeDAC-11 would not be able to fit into a system. The only things I can come up with is if balanced XLR outputs or 24/192 playback over USB is required. That’s when I remember that this is only a $350 device, and yet still outperforms the vast majority of (more expensive) units in terms of functionality.
 

 

 
Notice similarities between this internal layout and the other Yulong gear.  
 
BUILD QUALITY
The TubeDAC-11 has typical Yulong build quality, which I characterize as fairly high but obviously not “boutique”. It has solid weight to it. Surface gaps are tight and even. The volume and source selection knobs have a nice feel to them. I chose mine in all black to match the system I’m pairing it with, though the silver faceplate version does look very striking. Though I’ve seen it before with the D100/A100 units, the satin black brushed aluminum casing is no less visually appealing.
 
 
PACKAGE
Grant Fidelity really pulls out all the stops when outfitting the TubeDAC-11 with accessories. Aside from the unit itself the package includes a power cable, RCA interconnect, USB cable, toslink cable, coaxial digital cable, 1/8^th inch to ¼ inch headphone adaptor, and even a hex wrench for opening the case (required for tube rolling). This is one of the most comprehensive packages I’ve ever come across. Granted these are basic cables – they obviously can’t give out their reference quality stuff in a package like this. But it’s still pretty impressive and lets users get started immediately no matter what their system configuration may be.
 
The only thing “missing” that Grant Fidelity could possibly have included is an RCA to ¼” adapter. The rear Tube Out RCAs can be used to drive headphones directly under some circumstances. It is recommended for use with 300 ohm headphones or higher, though experimentation is always encouraged. I’ve had good and bad results with various lower impedance models which I’ll discuss later. In any case, this adaptor can be had for roughly $5 so it isn’t a significant issue.
 
 
EQUIPMENT
This is the associated equipment I used to evaluate the TubeDAC-11
 
Source: Lexicon RT20 universal disc player, JF Digital HDM-03S digital audio server, Pioneer Elite N-50 network audio player
 
Amplification: Violectric V200, Analog Design Labs Svetlana 2, Yulong A100, Matrix M-Stage
 
Headphones: Heir Audio 8.A, HiFiMAN HE400, Lawton Audio LA7000, Sennheiser HD700 prototype, Earproof Atom, AKG K240DF, Audio Technica W1000x
 
Speakers: Emotiva airmotiv5, Serene Audio Talisman Active
 
Cabling is by Signal Cable, music played ranging from CDs and 16/44.1 FLAC files all the way up to 24/192 releases. I let the TubeDAC-11 burn in for over a week solid prior to doing any listening.
 
 

 
Pictured with the older siblings: D100 and D18
 
LISTENING
My initial listening was done using the device as just a DAC via the DAC Direct output. I paired it with some headphone amps which are significantly more expensive, in an attempt to figure out just how much of a bottleneck the TubeDAC would be. The answer to that question? My initial suspicions were confirmed - the TubeDAC did a great job and integrated nicely into a quality setup. It seemed neutral and fairly grain free, with an ease about it that belied its modest price. From reference caliber recordings like Jazz Descargas by The Conga Kings (Chesky 24/96), to quality standard-resolution classics like Asante by McCoy Tyner (Blue Note), to downright poor quality releases such as Jimmy Eat World’s recent album Invented (Interscope), the TubeDAC-11 never felt like much of a weak link. It may not quite have the surgical precision of its sibling the Yulong D100 but the sound is definitely in the same family – which is a very good thing.
 
Already impressed by that point, I decided to switch inputs to document my experiences with each. With a device like this there is no real easy way to cover every inch of its functionality while keeping the review from becoming a novel. So I’m just going to note my observations of each section:
 
Solid State output (variable) - This section should theoretically sound very similar to the DAC Direct output. My experience proved this to be the case. With the preamp section in the signal path, there is a very slight reduction in detail. I would almost call it “softness”. But this is very difficult to detect: I had to do A/B switching for a long time in order to flesh out this difference. Even then, it’s not necessarily worse… just slightly different. I wouldn’t be surprised if someone preferred the variable output over the fixed choice. What isn’t subtle is the ability to adjust the output to whatever voltage your amp needs. This enables optimum pairing no matter what amplifier you choose. I’ve discovered that most amps are happy with roughly 2 Volts but some prefer a higher number. It comes down to trial and error, though I don’t usually crank the TubeDAC-11 up past 70% or so (which corresponds to roughly 4 Volts).
 
Tube output: The implementation here is somewhat different from what you might expect. Where the prior TubeDAC-09 had a tube preamp section paired with solid state output, the TubeDAC-11 is solid state in both sections. The tube portion here is actually used for buffering the output. There is a small collection of dedicated tube buffer devices on the market (some of which are actually sold by Grant Fidelity) that people will occasionally swear by. The TubeDAC-11 has that feature built in. Using the tube output imparts a bit of “sweetness” to the sound. It helps smooth out rough edges, especially in the treble region, and generally makes the presentation more musical. I some cases I perceived a slightly more expansive soundstage presentation, and I found this output to be fatigue-free in all but the most piercingly bright music/amp/headphone chains.
 
On the other hand, I occasionally felt like bass drum impacts were slightly less distinct through the tube output. A simple test confirmed this: Using the excellent airmotiv5 monitors from Emotiva, I played “Tears in Heaven” from Eric Clapton’s Unplugged. The opening section features some deep, impactful bass drum strikes, which are not supposed to be too prominent in the mix – yet they need to remain noticeable. The relatively compact airmotiv5s are no bass monsters but they dig just deep enough to handle this sound fairly well. With no variables in this setup it was clear from switching back and forth that the solid state output had better leading edges and made that kick drum sound the way I feel it should. The tube output was smoother down there and thus seemed less distinct. This was only detrimental on a few occasions, and I’d say that most of the time the tube output would still be my first choice. Realistically, all three outputs are very good.
 
I have not had time to swap out the stock Chinese 6N11 tube for something better. I suspect that there are very worthwhile gains to be had even with modest tubes and the price would remain low considering it only takes one. The TubeDAC-11 will accommodate some great sounding reasonably priced tubes such as the Genalex Gold Lion E88CC, the better Electro-Harmonix 6922 variations, and my personal favorite the Russian 6H23n-EB (available in NOS form at under $40). Any of these should go a long way towards improving the already good sound on the tube output. Of course it is possible to go way over the top with expensive tubes but one must keep in mind that this is a $350 device, so spending $400 on an exotic tube might not make the most sense.  
 
Headphone out: the headphone out sounds largely identical to the variable solid state RCA output – it’s clean, crisp, neutral, and fairly transparent. It has a nice quiet background and very respectable soundstage presentation. With no significant coloration, this headphone out is suitable for a very wide range of headphones. From very sensitive custom in ear monitors to relatively difficult to drive planar magnetic full sized models, the TubeDAC-11 is a very capable performer. The only limitation I see is the HiFiMAN HE-6, which has caused grief for quite a few dedicated headphone amps. But the vast majority of headphones out there will match up well. As is usually the case with all in one type machines, there is a gain to be had by adding a stand-alone headphone amp. But I like the fact that the TubeDAC gives a very solid baseline from which most people wouldn’t be tempted to upgrade until they get really serious about headphones. Even then, I don’t feel short changed when listening to a $1k+ headphone with straight from the TubeDAC. Remember that we are dealing with a quality opamp plus discrete buffer design and a nice power supply – much more advanced than a typical chip amp driven by a wallwart that you might find in other do-it-all models from other brands.
 
Alternative headphone amp: An interesting option is the ability to use the rear panel Tube Out RCA outputs with an RCA to ¼ inch adapter, allowing headphones to be driven straight from the tube buffer. Grant Fidelity lists this as generally being for 300 ohm headphones or above, though as always individual results may vary. I found that the 42 ohm Audio Technica W1000x sounded pretty good – arguably preferable to the dedicated headphone amp. I also really liked the 600 ohm AKG K240DF on the tube out – the bit of extra warmth and smoothness is just what the doctor ordered for extended listening with these borderline overly-analytical cans.
 
The fact that Grant Fidelity does not include the required adapter in their otherwise exhaustive accessory package tells me that they don’t want people expecting too much from this option. That’s probably not a bad thing – roughly half of the headphones I tried sounded somewhat poor. But the other half sounded pretty interesting, and several of them made excellent matches. So I think it is worth exploring for headphone aficionados. The adapter is roughly $5 so why not?
 
USB: I’m not usually one to find major differences between coaxial, toslink, and USB inputs. And again I don’t find any major discrepancies with the TubeDAC-11. I think SPDIF has the potential edge when being fed by a very low jitter source. But the USB is more consistent since any decent netbook or desktop computer can get the job done just as good as a more powerful counterpart. The sound here is good enough to notice differences between various software playback choices – a phenomenon I’m still not quite sure I understand. Grant Fidelity does provide ASIO drivers specifically for this device, though I also had success using WASAPI mode. Both options sound equally competent and I wouldn’t hesitate to use this device with USB as the primary source. The one drawback is common with all devices using the Tenor TE7022 receiver – no support for 88.2kHz sample rates. 
 

 
 
COMPARISONS
The TubeDAC-11 sits in an interesting position in between true budget models (which I define as being under $200 or so), and “entry level high-end” choices (which I vaguely define as $500-1000). It’s good enough where someone who set out to spend $200 might want to save more and step up to the TubeDAC. It’s also good enough where someone prepared to spend well over $500 may not need to. I do happen to have a few competitors on hand which go for roughly the same price range, and I think the TubeDAC stacks up quite well.
 
Matrix Cube
The Cube is an excellent compact all in one DAC/amp. It goes for $50 less than the TubeDAC and has a defeatable sample rate convertor option which helps eliminate jitter. In exchange, the TubeDAC gains preamp functionality, hi-res over USB, and of course the tube option. I’ve always enjoyed the warm fun sound presented by the Cube but I don’t think it is quite on the same level as the TubeDAC. In particular, the Grant Fidelity unit makes the Matrix sound a bit slow or syrupy. Resolution is higher and general transparency is superior. The Cube does have the edge in soundstage clarity and depth which I’ve always found to be its strong points. But aside from that the TubeDAC is the superior unit. Note that my Cube is the older model without socketed opamps; the new versions allow opamp swapping and perhaps that would enable the unit to compete better. I still don’t think it will quite be able to keep up though.
 
Audiotrak Dr. DAC2 DX Muses Edition
I’m still working on the review of this little guy. It’s a very nice unit, a perfect upgrade to those who enjoy the Audinst HUD-mx1 but want to go a step farther. Like the DAC-11, it features a surprisingly complex design, with quality opamps driving a fairly complex array of discrete transistors for the headphone out. It is able to match the TubeDAC in some ways – preamp functionality, hi-res USB, and an overall clean neutral sound. Both are very clear and transparent, with good soundstage presentation and believable timbre. The Audiotrak has slightly more forward mids which makes it a better match for certain headphones (Denon) but worse for others (Audio Technica). It also has more gain on available for driving the HE400 to ridiculously loud levels…. Not that I would ever need to do so. The key difference for me is that the TubeDAC seems able to dig deeper, delivering more impressive low frequency response when called upon. I’m guessing this is attributed to the more robust linear power supply on tap as compared to the wall wart used by the Audiotrak unit. And once again the Grant Fidelity choice has more usability overall. But the Audiotrak does have a few tricks up its sleeve: it can function as a USB to SPDIF converter, it can pass through Dolby Digital files through its optical output, it has dual headphone outs…. And most importantly, it is really really small. That last bit is the reason the Dr. DAC is currently residing in my computer rig feeding a pair of Serene Audio Talisman Active monitors. I’d love to use the TubeDAC there but there simply isn’t room.  In terms of pure audio quality, the TubeDAC-11 remains unbeaten in its price category. Obviously I haven't heard every single DAC out there in the sub-$400 range. But a recent audition of the new Cambridge DACMagic 100 ($369) and the Music Hall DAC15.2 ($299) only confirms my high opinion of the TubeDAC-11. 
 

 
Stacked with D100, D18, and Anedio D2
 
 
CONCLUSION
The Grant Fidelity TubeDAC-11 is a stunning example of just how much you can get for your money these days. It has so many functions and not one of them is a weak link – each is well implemented and performs to a very high standard. The nex cheapest product I can think of that offers this much functionality in such a small box (the Matrix Quattro DAC) goes for twice the price. I can absolutely see the TubeDAC acting as the very capable heart of many an audio system.
 
One must be smart these days – after all, $350 is still a lot of money. If you are strictly looking for a stand-alone headphone amp, or a DAC with USB input only, then the TubeDAC-11 may not be on your radar. Then again, being smart means realizing that your system may expand, and planning for that occurrence. In that respect the TubeDAC-11 has you covered. You just have to get over the idea that more features for the money equates to some compromise. That’s just not my experience with this device.
 
I commend Yulong for once again delivering a stellar product for a reasonable price, and I commend Grant Fidelity for making the right choice in aligning themselves with Yulong. In my humble opinion there is simply no better buy at $350 than the TubeDAC-11.    

 
 
 
Pioneer Elite N-50
 
 
 

 
 
I’ve been covering media streamers, network audio players, or whatever you want to call them, as often as I can around here. I think HeadFi is a great audience for these types of devices – we are generally younger and more knowledgeable about computers than your average “The Absolute Sound” reader. Or at least that’s my assumption; I could be wrong. But I do see a large percentage of folks around here who completely rely on lossless audio files instead of spinning their original CDs. So I’d say we have a pretty good demand for devices that help tap in to those files.
 
But isn’t it easier to just play them straight from your computer? There is already a plethora of excellent choices in the realm of USB DACs, spanning all price points. Why spend extra on a stand-alone device to accomplish what your computer will already do? In my Streaming Audio Devices review and information thread, I lay out the reasons like so: some people don’t want to mess with having a computer in their playback system. The system is probably in a dedicated area, away from their desktop computer. They don’t want the noise associated with the computer, nor do they want a monitor in their system. They don’t want to bother with playback software, configuration, and the inevitable troubleshooting that computers bring. They just want something simple that can act as a relatively foolproof front-end, that will sit next to their pre-amp and other gear and not look out of place. In short, they want the benefits of having their entire library at hand, including hi-res downloads, while retaining the simplicity and ease of use that a regular CD player would have. That’s why I think these types of devices are important.   
 
Pioneer recently launched their first entries into this category. The N-50 (and little brother N-30) aims to compete with the NAD C 446, Denon DNP-720AE, and Marantz NA7004 full sized components rather than devices like the Logitech Squeezebox Touch. I’ve spent some time with the N-50 and think it has some very strong points, along with some smaller aspects that could be improved. But for the right type of user this could be a great match.
 
 

 

 

 

 

Optional wireless unit
 
 
DESIGN
The N-50 is branded as part of Pioneer’s “Elite” line of components. Back in the day that meant something very significant. You could count on the Elite line to be far better than your average audio/video components. Somewhere along the way, it seems like the Elite brand got watered down. Instead of classic models like the DV-09 and DV-38a (each costing several thousand dollars), it ended up with gear like the DV-46AV and DV-49AV, each just a few hundred dollars. It looks like Pioneer is now bringing the Elite brand name back to where it belongs.
 
The N-50 is a stand-alone component roughly the size of a higher-end CD player. It has quite a few tricks up its sleeve: AirPlay compatibility, DLNA support for network playback, internet radio, USB port for direct playback from a flash drive, and dedicated remote apps for Apple and Android devices. Another standout feature is the set of digital inputs which allow the N-50 to perform DAC duty: it has toslink and coaxial SPDIF inputs as well as an asynchronous USB input. I’m not aware of any competing device with a high end USB implementation like the N-50.
 
On the front panel, you’ll notice the 2.5 inch LCD display. Next to that are control buttons allowing full control of the transport and menu functions without needing a remote. On the left side you find a power button and a USB port. On the rear we see the array of digital inputs – toslink, coaxial SPDIF, and USB. There is also toslink and coaxial digital outputs along with the single ended RCA analog outputs. An Ethernet port allows wired connectivity, and two separate jacks accommodate the optional add-ons for wireless connectivity. The first (and more important) is a USB port dedicated to providing power to the Pioneer WL300 wireless adapter, which also plugs into the Ethernet jack. The second is a proprietary slot for the ST200 bluetooth adaptor.
 
Internally, the N-50 is fairly complex. Pioneer isolates each section on its own PCB, presumably under the guise of reduced interference. So there is a main board that handles the processing, another board for the power supply, and another for the DAC section. The analog and digital sections each get their own separate EI core transformer. The USB input is handled by the C-Media CM6631, and the other two digital inputs go through an AKM AK4118 DIR. All three inputs can handle up to 24-bit/192kHz data streams. Since the DAC board is facing “down”, I can’t get a look at the design. I know it is based around a 32-bit AKM AK4480 DAC, which Pioneer has recently used in a few other Elite series disc players and surround receivers. It is also used in the Fostex HP-P1 portable DAC/headphone amp device. I confirmed with my contact at Pioneer that the N-50 is a completely new design – it does not borrow elements from the other Elite products.
 

 

 

 

 

 

Top side of analog section - the good stuff is facing down
 

Hard to see, but this is the Cmedia 6631 asynchronous USB receiver
 
 
BUILD QUALITY
The N-50 reminds me of the old Pioneer Elite disc spinners from back in the day, minus the rosewood side panels (unfortunately). It weighs in at 16 pounds and has a nice thick brushed aluminum front panel. While it is not likely to be mistaken for a product from McIntosh or Accuphase, it nonetheless feels like a high quality unit, more than appropriate for its price range. The remote has a solid feel to it as well. It’s passable from a usability standpoint - long and skinny with a fairly good placement of buttons. But honestly the target user for this device will almost certainly have an Apple or Android device to use as a remote. Pioneer has dedicated software on both platforms for that purpose.
 

 
 
USE
Reviewing a player like this calls for a special section that I don’t normally include when covering a DAC or amp. Since the main function of these devices is to replace the computer or CD player, they become the main point of contact for the entire system. So they need to be relatively easy to deal with during day to day operation. The N-50 succeeds here on most levels. The menu structure is very straight forward – if you can handle an iPod Classic or Sansa Clip, you should easily feel at home with the N-50. I do wish Pioneer had included wireless capabilities out of the box instead of requiring the $150 add on. It took me a few tries to get the WL300 wireless adapter to pair with my router. Once you’ve got it up and running though, it is fairly smooth sailing.
 
My chief complaint with the whole experience is the size of the screen. At just 2.5 inches, there simply isn’t much room to work with. The fonts used are therefore very small, and you get a tiny little square for album art. It worked just fine when used in a headphone rig: the display was adequate when sitting a few feet away, and I appreciated having the transport buttons at hand. But sitting on a component shelf across the room is another story. Even with perfect vision, the display was simply too small to be useful. Obviously if I used my iPad as remote then I had all the info displayed there. But that defeats the purpose of having a display on the device in the first place. I couldn’t help but notice the large area in the center of the front panel that was left unused.  It looks like Pioneer gave more real estate to the “Elite” logo than the screen itself. This seems like a missed opportunity in an otherwise well thought out design.
 
Like many of these types of devices, metadata and artwork is a hit or miss affair. This really has more to do with your files being configured properly in the first place than it does with the N-50. If Windows Media Player finds the art and the tagging, chances are good that the N-50 will display them. But if you just purchase an album from HDtracks, throw it on a flash drive, and plug it in to the N-50, you will probably not get the art to appear. Again, this is common among all the network audio playing devices I’ve tried.
 
The dedicated software for iPhone/iPad is nothing special. It gets the job done by allowing you to power off/on, select your source, switch tracks, etc. But it doesn’t look particularly appealing. You don’t even get album art displayed during playback. Scrolling through long lists of tracks or artists can be tedious because it lacks any kind of search options. Frankly, I ended up using other software to select my music, only going back to the Pioneer app when I needed to power off. But I’m still glad that they included some type of dedicated software, unlike NAD with the C 446 device.
 
 

Main menu
 

Basic play screen 
 

For some reason it only uses half the screen
for listing files
 

Browsing
 

Sorting
 

Airjam is for use over Bluetooth - multiple devices can join in
and stream to the N-50. This would actually be kind of fun in
a workplace or dorm setting as background music.
 

Airplay is easy
 

Airplay again, through another program
 
 
 
EQUIPMENT
This is the equipment I used during my evaluation of the Pioneer N-50:
 
Sources (used as transport): Lexicon RT-20, Logitech Squeezebox Touch, JF Digital HDM-03S music server, Acer Aspire One laptop
 
Amps: Violectric V200, Analog Design Labs Svetlana 2, Matrix M-Stage
 
Headphones: Sennheiser HD700 prototype, Audio Technica W1000x, Heir Audio 8.A, Unique Melody Merlin, Aurisonics AS-1b, Earproof Atom, Lawton Audio LA7000
 
I also listened through a speaker setup using the N-50 as source, ADLabs Svetlana 2 as preamp, Parasound 2125 amp, and Octet Matrix DE7 speakers. All cables used were from Signal Cable, with power conditioning by Furman. I burned the N-50 in for over 100 hours prior to doing any serious listening.
 
IMPRESSIONS
The N-50 is simply a great sounding machine. A lot of effort clearly went into the design, and the result is obvious in terms of audio quality. Everything sounds clean, detailed, mostly neutral but not overly analytical. It has a sort of smoothness up top that doesn’t scream “digital!” but retains very good extension. It’s a tough thing to balance and I’ve heard plenty of DACs costing more than this entire device get it wrong. With better headphones or my speaker setup, the N-50 produced solid imaging and a moderately large soundstage. It didn’t have the last bit of realism that comes with much more expensive DACs, though I think all but the most demanding audiophile would be pleased with the overall presentation.
 
I really enjoyed the capabilities it had to play almost any type of file I threw at it. Listening to McCoy Tyner Quartet’s New York Reunion in 24/96 format, I was struck by the way the N-50 handled Al Foster’s excellent drumming. This is a guy who played with everyone including Miles Davis (for over a decade), and is one of my all time favorite percussionists. On track number one “Recorda Me”, I love the way he seems to take a back seat to his bandmates, supporting their solos with competent but low key grooves. About half way through the track, it strikes me just how much he is actually doing. In a subtle way, without calling attention to himself, he’s being extremely creative with ride cymbal variations and all kinds of clever fills. It’s all there if you want to hear it, but it doesn’t jump out at you. I’m sure there is a metaphor in there somewhere about the performance of the N-50 but I’ll let you make that connection.
 
The 24/192 capabilities over USB came in rather handy. Many DACs stop at 24/96 over USB, which is good enough to play most of my collection. But what about my HDtracks 24/192 edition of Marvin Gaye’s What’s Going On? Or my small collection of 24/192 vinyl rips? Those types of files are becoming just common enough in my library to be a nuisance if the DAC tops out at 96kHz. I also appreciate that the N-50 gives me several ways to handle these types: USB from my laptop, coaxial digital from my music server, even streaming via DLNA or Airplay. Unfortunately I ran into buffering issues with both methods of wireless streaming. At times I would make it through several tracks without issue. Other times I got buffering so badly that I had to find 24/96 or lesser files to play (which always worked without any problems). I’ve got a fairly robust 802.11n home network but perhaps others will have better luck. An Ethernet connection may do the trick, though at that point you’ve lost the main advantage of the networking feature since a direct asynchronous USB connection would be just as easy (since you would be in proximity to the computer anyway).
 
A few limitations of note – the N-50 will not play higher than 24/96 from a flash drive plugged into the USB port. I figured USB drives would be faster and more reliable than the network streaming but apparently Pioneer disagrees. Files above 24/96 just show up as an invalid format. Also, the device doesn’t support ALAC or AIFF file formats. I use Windows 7 and store all my music in FLAC format with a few exceptions for WAV and (gasp!) 320k mp3, so this was not an issue for me. With users of the “other” operating system, this would be a serious handicap indeed, quite possibly a dealbreaker. Yet another limitation is the streaming of 24-bit/176.4kHz files through the USB DAC connection. Apparently the issue lies with the Cmedia 6631 USB chip, and it is a driver issue rather than a hardware limitation. The Schiit Bifrost DAC uses the same chip and has the same problem. A friend brought this to my attention after I had already sent the N-50 back to Pioneer. So I didn’t test this myself, though I did play Reference Recordings HRx tracks at 24/176.4 via coaxial SPDIF without issue. This is one problem that should be able to be addressed via software updates to the drivers once they get the bugs worked out.
 
While we’re on the topic of limitations, another one bothered me just a little: no support for hard drive connections over USB. I had success with all the flash drives I tried, from 2GB to 16GB. But a portable USB powered 500GB drive failed to work, as did a self powered 2TB drive. My contact at Pioneer told me that it may be possible to enable this feature down the road but it is not planned at this time. The difficulty is due to the varying power requirements of portable drives. That makes sense to me and NAD handles their USB connection the same way. I’m still not clear on why a stand-alone drive with a separate power connection shouldn’t work though – the Squeezebox Touch is able to read those just fine.
 
But back to the sound - the best sound I heard from the N-50 was when I used it as a DAC through the asynchronous USB connection. Those who are familiar with my style know that I’m not usually one to hear major differences between various digital inputs. In my mind a good design should have little to no audible differences across all the inputs. Every once in a while I come across a product where one of the inputs (usually toslink but not always) sounds clearly inferior to the rest. I believe the N-50 is a bit different – rather than one of the inputs being compromised, it’s actually the advanced nature of the asynchronous USB connection that pulls ahead of the standard SPDIF alternatives. I don’t see any specific jitter reduction techniques applied here aside from what takes place in the digital audio interface receiver and the DAC chip itself. So the asynchronous connection very likely has the better numbers in that regard. Not to say the other two choices sound bad by any means – the difference is slight but noticeable when connected to a highly resolving system. USB also has the advantage of being more consistent. Feeding high jitter SPDIF signals from a cheap DVD player sounds clearly inferior to using a quality transport.
 
Going a step further, I get the impression that the N-50 just doesn’t sound as good playing music through the network. There seems to be a general loss of clarity and resolution, particularly with respect to the “airiness” of the presentation. Imaging and soundstage capabilities suffer a bit due to this loss. It’s not terrible – the N-50 is still a very competent sounding device when streaming over the network. It just isn’t at its best that way. I wonder if this is some issue that could be fixed via software updates, because I can’t think of any good reason why it should be so. When using the N-50 as transport with an outboard DAC featuring comprehensive jitter reduction, such as the Violectric V800 or Anedio D1, the resulting sound is excellent. When I use a more basic DAC I don’t get much improvement over the analog outputs. I suspect that the networking process has much higher jitter than the other inputs. Still, I remain impressed with the sound overall. You would have to step up to something above the level of a Cambridge DACMagic (for example) in order to see any potential improvement.
 
I spent a lot of time going back and forth between the sound modes. Aside from the standard playback, Pioneer gives two main options for tweaking the sound, or three if you could the “sound enhancer” which only applies to compressed files (I didn’t bother with that). The mode which gave the biggest difference in sound is called “Hi-Bit 32”. Pioneer doesn’t go too far in depth about this technology other than to say it “expands the input bit signals to create a natural and analogue-like waveform”. They specifically mention 24/192 signals being “expanded” to 32/192, but also mention standard resolution “CD audio” as well. They show a tiny picture of a waveform – jagged in 24-bit form, much smoother after 32-bit processing. I’m not really sure what to make of that idea. There are plenty of solid reasons why sample rate upconversion can help improve the audio experience. If a 16-bit track is involved, it generally gets padded to a bit depth of 24. But very few companies in the audio world opt to quantize to 32-bit, and I’m not convinced there is really any valid reason to do so. Despite that, I thought I heard subtle changes when switching to Hi-Bit mode. With some tracks there was an illusion of more spaciousness, more air in the presentation. Other times it was completely unnoticeable. It was subtle enough to have just been my imagination though. The other option is something Pioneer calls “Pure Sound”. This is said to bypass the DSP circuit, thus “reducing noise and producing playback sound with the greatest fidelity to the original.” Pure Sound can’t be combined with Hi-Bit 32, and the way things are worded Pioneer can’t seem to decide which is most important. To my ears, Pure Sound did not make any audible difference. I did end up leaving Hi-Bit mode active during most of my listening.
 
CONCLUSION
The Pioneer N-50 is an interesting device. In theory, it is a network audio player that can also be used as a DAC. In practice, it is best used as a DAC that also happens to have network audio functionality. It’s a subtle distinction, one that I’m not sure Pioneer was really aiming for, but that’s how I see this device. It sounds pretty great no matter how you use it – even with network streaming it has a clean and smooth sound that is fairly articulate but not overly analytical. This sort of sound signature should be pleasing for the majority of users. I think it falls just slightly behind the NAD C 446 when used as streaming player, but surpasses that unit when used as a DAC, especially over USB.
 
The fact that it sounds best as a USB DAC might seem strange – if that’s the case, why not just buy a dedicated USB DAC instead of this network device? Realistically, this is a very strong competitor at $700 even if used strictly as a DAC. I can think of several highly regarded DACs with 4 figure price tags which do not perform as well in many respects. In my mind, this is quite an accomplishment for Pioneer.
 
Functionally the N-50 has a lot to offer. There are so many ways to get music in or out of the device that it should fit into any system in one capacity or another. The unit is very easy to operate when playing tracks over a network and even more simple when using Airplay. The biggest difficulty of the whole operation will be organizing your music files with the proper metadata. But that’s not Pioneer’s fault.
 
Ultimately I think the N-50 has a lot of promise, and delivers in many areas. Yet it could use a bit of fine tuning. It isn’t the magic bullet for network audio players (but nothing is at this point). I’d love to see the display expanded to useable proportions. I’d also like wireless connectivity built in. Support for USB hard drives would be also great, as would support for ALAC and AIFF files. Most of all I’d like it if Pioneer was able to bring the network playback sound quality up to the same levels as the digital inputs. With just a few relatively minor yet important changes, this device could become a clear leader in the segment. And if there was an updated model with a larger display, it would be unstoppable. As it stands the N-50 is still a very nice product overall, and worthy of serious consideration.
 

 

 

 

 

 

 

 

 

 

 

 
 
 
I think it is safe to say that the headphone market is on an upward swing. Headphones are no longer relegated to being niche products, but have become far more mainstream than ever before. We are seeing growth in all categories, ranging from budget models to celebrity endorsed overpriced gear, and even very expensive flagship products. In ear monitors have kept up with their full sized brethren in terms of having more brands making good products than we’ve ever seen. As a subsection of the IEM category, custom molded IEMs have arguably had the most growth of all.
 
Go back a little ways and read some old threads on HeadFi – you won’t find many discussing customs, and when you do it seemed to be limited to upscale folks who already had pricey Stax or other rigs. I’d say very few average music fans were actually interested or even aware of customs back then – and for good reason: most of them came in at $600-800 or more. Frankly, as someone who owned some of those early models, I don’t know if the sound quality was there in comparison to similarly priced full sized models.  But these days things are different. Instead of a handful of choices, we have well over a dozen custom IEM companies to choose from.
 
There are a few different types of custom companies out there. Some of them have been around for a long time, such as Westone or Ultimate Ears, and are well known all over the world. Others are newer such as Unique Melody and Heir Audio, but are aggressively trying to expand worldwide with their excellent offerings. But there is another type, which is actually more common than you might think: the small time company who is not really interested in becoming a worldwide player. Instead, they are content to serve their local market, often doing so for many years without any recognition outside of their home region.
 
One such company is Earproof. Based in the Netherlands, Earproof has been making custom products for monitoring as well as hearing protection for about 8 years now. They attend many events such as concerts and festivals, and have a big focus on raising awareness about potential hearing loss caused by excessive volume in these types of venues. They offer a wide range of earplugs and monitoring products for musicians as well as security/law enforcement, news media, and others. Despite all of this, I had never heard mention of them on HeadFi. So I decided to contact them to see if they were interested in changing that.
 
Peter Van Galen is the man in charge at Earproof. After some discussion, he told me to send in my ear impressions, and he’d come up with something. A short time later I received a non-descript package in the mail. A handwritten note from Peter said something to the effect of “These use the smallest drivers on the market. They won’t get super loud, but I hope you enjoy them. –Peter”. Accompanying the note was a pair of custom molded IEMs – in white silicone, with a very small form factor, the product was called the Earproof T3i. It sounded remarkably clean and clear in an Etymotic ER4S sort of way, but unfortunately one side had some type of driver damage, producing distortion at nearly all volume levels. Back to Earproof they went, with Peter promising to find the problem and fix it.
 
That was just the beginning of what ended up being roughly 7 months of waiting. It seems that Peter had an idea for a new design, and he wanted to perfect the sound before sending it out. I waited patiently, and a few months ago a package arrived again. Though externally identical to the T3i, this new product sounded even better than the previous incarnation. Peter finally gave me the details – the new design is called the Earproof Atom. It uses the dual driver version of the tiny balanced armature driver used in the T3i, for a much more full range sound delivery. The price was set at $469. I was excited to give it a listen, and I’ve been using it almost daily for a while now.
 

 
DESIGN
As you can tell from the pictures, the Atom is a very small format custom IEM. It inserts in the canal portion of the ear, and is hardly noticeable from most angles. The shell is made from an extremely soft silicone – I can bend the canal portion back to the base in a U shape if I wanted to. This makes for a very comfortable fit, and probably the best seal I’ve ever encountered from a custom IEM. Isolation is very good, though I suspect a small amount is lost due to the “canal only” type design. Sounds can still resonate through the remaining portions of the ear which the Earproof Atom leaves bare.
 
As is nearly always the case with silicone shell custom IEMs, the Atom has a non-detachable cable. Peter advised me that he was unhappy with the current solution due to issues with microphonics, so the cable on my pair will not be the final design. I do find the cable slightly prone to tangling, and the microphonics are worse than the standard Westone-style braided cable. So if Earproof has a better cable in mind than this Kevlar-reinforced design, then it can only be a good thing. That said, this cable is certainly not bad. It protrudes in an upward fashion so it is clearly meant to be worn over the ears. In retrospect kind of I wish I had asked for mine to exit at the bottom to be worn straight down, though I don’t even know if that is an option.
 
Inside, the Atom is based around a Sonion 4400 dual balanced armature driver. This is a tiny thing - even smaller than the popular TWFK dual driver unit from Knowles Acoustics which is used by many IEMs of both the universal and custom variety. Sonion was heavily involved in tweaking the overall design to achieve optimal results. Nominal impedance is 70 ohms and sensitivity is 105dB. As I’ll discuss later, these specs are misleading – this is one tough IEM to drive to full potential.
 
In terms of colors and designs, the Atom is offered in clear or white. I got white. Mine have the red Earproof logo on the right side and a blue logo on the left side. I assume this is standard though you could probably request to leave them blank. There isn’t much room for a fancy design so I doubt Earproof lets you submit your own artwork, but I never specifically asked.
 

 
 

 
 

 
BUILD QUALITY
Despite having more custom IEMs than I care to count right now, this is actually my first full silicone model. I’ve had the Westone ES3X with the tips made of vinyl but that was nowhere near as pliable as these. I don’t know how to really gauge quality in a case like this, other than to say that the shell is completely smooth, appears well made, and fits perfectly. The cable (again not the final production version) is sturdy and seems like it would last forever. It has no memory wire for keeping the loop around my ears, but I found that cinching the cable after the Y-split to be somewhat snug to my neck keeps it perfectly in place no matter what I do. So overall I’d say build quality is quite good from my limited experience. I think the white color is well done; the “clear” silicone customs I’ve seen always appear cloudy compared to a good acrylic shell. I think that’s just a property of the material, and doesn’t say anything about the build quality, but that doesn’t mean I have to enjoy it. So I’m pleased with the white.
 

 

 

 

Apologies for the blur, here is the flexibility I mentioned. 
 
PACKAGE
Since this wasn’t a retail package, I didn’t get much in the way of accessories. The IEMs themselves, a semi-hard shell storage case, and a printout of the frequency response chart. A person ordering these might get a whole lot more, or might just get the same kit, I’m not sure.
 

 
 
EQUIPMENT
Here is the equipment I used to evaluate the Earproof Atom:
 
Portable: Sansa Clip+, Sansa Fuze, QLS QA350, hiSound RoCoo D Power Edition, TCG T-Box amp, Audinst AMP-HP
 
Home Sources: Squeezebox Touch, JF Digital HDM-03S music server, Pioneer Elite N-50 network player
 
DACs: Anedio D1, Yulong D100, Violectric V800, Yulong D18, Matrix Quattro, Kao Audio UD2C-HP
 
Amps: Yulong A100, Violectric V200, Analog Design Labs Svetlana 2, Matrix M-Stage
 
Music was a variety of genres, almost always in FLAC format ranging from 16-bit/44.1kHz to 24-bit/192kHz and everything in between. Cables are all by Signal Cable, with power conditioning by Furman. The Atoms were burned in for well over 100 hours prior to serious use and by now have quite a few more hours on them.
 
Here is a size comparison between the Atom and a regular sized custom:

 

 

 
 
LISTENING
My initial experience with the Earproof T3i was interesting. It sounded very fast and clean, with surprising low frequency extension for a single driver balanced armature design. But it was limited in dynamics and suffered from some unfortunate harshness in the upper regions, which I don’t believe was related to the faulty driver issue. Given the price that I thinkEarproof was asking for them (the website is confusing), and the loss during conversion to US dollars, I could not imagine recommending them considering how strong the competition is in this segment. But the Atom is a whole different story. It has twice the drivers, which helps address the shortcomings of the T3i, and it sells for under $500 USD. Now we’re talking.
 
Even though this is a dual driver design, it is still billed as the world’s smallest dual driver. So I was expecting something fast, detailed, clear and extended in the treble, but still lacking in overall resolution and weight. I was surprised to discover that not to be the case. The Atom can unexpectedly kick you in the pants when the music calls for it - with the right amplification. The more I listened, the more I started hearing traces of some of my favorite full sized headphones. Some HD600, some W1000, a bit of K701… yet overall the Atom has a unique sound that can’t be summed up with just a single “sounds like” comparison. But allow me to explain further.
 
Once again – with the right amplification, the Atom has rich, deep, fast bass capabilities. On quantity it is roughly in line with a well driven HD600, meaning a bit more present than the K701. In terms of quality, it is right up there as well, though I perceive slightly more sub-bass impact with the Atom than either of those full sized models. That might just be the effect of pressurization from a sealed ear canal, rather than the open full sized models, but I appreciated it.
 
The speed and attack of the bass is just startling – I enjoyed listening to some of my favorite punk bands like Dogwood, Lagwagon, and NOFX, with the Atoms easily keeping up with the fast paced double bass drum action. The downside is that it really prefers good recordings, which is not really the usual description of this genre. Some of my albums sounded thinner than others, but the better ones sounded really great.
With bass heavy music, the Atoms provide a nice impact in a sort of “reference” way, but they don’t quite rattle your skull. They do better at “punch” than “rumble”. In this way they remind me of the Sennheiser HD800. Everything that should be there is there, beautifully and faithfully recreated. The textures are rich, and you can really distinguish one sound from another. Yet there are times when you wish for some more “oomph”; a more realistic portrayal of actual air being displaced by a big woofer. The Atom (and the HD800 for that matter) doesn’t quite do that in the way that something like the Heir Audio 8.A can do, or even a budget model like the Westone AC2. But the Atom is more accurate and quick in the bass than the AC2, so it is a bit of a tradeoff.
 
Mids strike a nice balance – not forward, not recessed. It would be easy for them to be on the prominent side in relation to those quick, tight lows, but Earproof does a fantastic job of keeping them neutral without making them too dry or boring. Vocals of all types sound very well done, though again better recordings really shine. I spent a lot of time listening to Nancy Bryan’s debut album “Lay Me Down”. I have the CD in the JVC XRCD format and I’ve always thought it sounded amazing. But I recently discovered a hi-res release in 24/96 from HDtracks. Her voice is stunning on tracks like “Blood Song” and “In and Out of Time”, and I believe the hi-res version clearly shows its superiority. Not all headphones are capable of resolving that distinction but the Earproof Atom apparently is.
 
I appreciate the lack of graininess in the upper mids and highs. While not quite electrostatic smooth, the Atom is one of the smoother IEMs I’ve heard at any price, while still remaining detailed. Even the classic Etymotic Research ER4 models have a bit of grain standing between you and the music. The Atom is virtually grain free.
 
Highs are crisp and well extended.  There is almost a complete lack of sibilance here, which again highlights the balance achieved. Some IEMs try pushing too much detail, resulting in sibilance ruining the fun. Others go too far in the name of smoothness and omit some details, meaning it doesn’t quite sound like a real person there in front of you performing. The Atom has just enough crispness to let you hear those subtleties without over blowing them, turning them into the musical main event. They don’t quite have the same sparkle as something like a UM Miracle, but they would only seem lacking with direct comparisons. On their own I never felt them lacking.
 
Soundstage is potentially a weak point here. Not that it is bad per se, but it is on the smaller side compared to some of the similarly priced competition. Instrument placement is very accurate, and it seems the focus is placed on defining the performance space rather than making it huge. This is in line with the general presentation that these give, which is closer to a nearfield studio monitor than a hi-fi speaker setup. I call it a weak point because I know some people prefer the bigger presentation, though personally I find that the Earproof approach “works” just the way it should.
 
I made it a point to talk about “quality amplification” during the above comments. Though all the custom IEMs I’ve heard have shown some benefit from a better source and amplification, the Atom is in another category – it seemingly requires something better than your average DAP. Maybe it is the 70 ohm impedance that causes most players to stumble, but I didn’t enjoy it much from a Sansa Fuze or Clip+. I could go to maximum volume and it would just barely be loud enough, or almost loud enough depending on the music. In most cases with other IEMs, full volume on a Sansa will blow out my ears. So despite their tiny size and low driver count, the Atom is up there with some of the most advanced 6 and 8 driver models I’ve heard in terms of system matching.
 
On the go, I liked it most from the hiSound RoCoo D Power Edition, which is normally supposed to do best with headphones rather than IEMs. I also liked it with an iPod 5g running Rockbox, using an LOD and a portable amp such as the Audinst AMP-HP. But the real fun began when I tried it with my bigger home equipment. IEMs with a big tube amp? Not usually, but in this case, absolutely! My single ended triode amp from Analog Design Labs sounded fantastic with the Atom, giving it enough refinement to be up there with much more expensive models. It also sounded wonderful with my high-powered Violectric V200 amp, maintaining a silent black background despite the several watts per channel on tap. Even something as simple as the built in headphone amp on my Grant Fidelity TubeDAC-11 was a huge step up from the portable experience with a standard DAP. I’m not quite sure how I feel about this. On one hand, I’m a big proponent of traveling light and not using a portable amp when possible. The Atom is not my first choice in that scenario. On the other hand, I really appreciate how high it scales on better equipment. In that respect it goes much farther than a dual driver model has a right to go, and the results are very impressive.
 

 
Here is the frequency response chart as provided by Earproof. It indicates a clear, detailed sound with good extension on the low end, a bump centered around 3.5 kHz, followed by a sloping roll-off to 10kHz. From there it picks back up with some good response to around 15kHz, then a final roll-off from there on up. The general shape of the chart is not so different from Tyll’s uncompensated measurements of the Etymotic ER4 and the Phonak PFE112.
 
I was a bit concerned about the THD measurements in the lowest frequency range under 40Hz or so. Overall levels are low with that exception. I browsed Tyll’s measurements and found that it isn’t too far off the norm compared to other armature based designs. The Grado GR8 for example is higher across the entire board, though it comes at higher playback levels too. Ultimately this supports my listening impressions that the Atom is not meant to be played extremely loud. Given the level of isolation it offers, I don’t find this to be an issue.
 
COMPARISONS
Competing products would generally be any custom IEMs in the sub-$500 range. I’ve got a few of those handy for direct comparison.
 
Westone AC2: These two couldn’t be more different. Though both have dual drivers, the AC2 has a massive driver dedicated to low frequency reproduction and a smaller unit for highs. The Westone has plentiful bass – some may find it overbearing. It is fairly high quality but the Atom has the edge in terms of tightness and control. AC2 has more distant mids, and sharper highs. The Atom is more articulate, more neutral, and cleaner in terms of grain and sibilance. The AC2 has a much larger soundstage. The AC2 is very easy to power, though benefits from smoother sources.
 
1964-Ears 1964T: This time we have a triple driver model against the dual driver Atom. The 1964T is fairly neutral, with a slightly tipped up bass region and a bit of a downward tilt on the highs for a warm relaxed feel overall. With two very large bass drivers, the 1964T is capable of bigger bass than the Atom, though again I think the Atom has a slight edge in bass clarity and speed. The Atom has a more crisp presentation with everything being right there in front of you, but not overly aggressive. The 1964T handles music in a more easy-going manner. Once again the Atom is more difficult to drive.
 
In general I believe there is a pattern here: the Earproof Atom is very competitive in its price category. It takes significantly more power to “wake up” than its rivals, and may seem a bit uninspiring until you properly drive it. Once given a good source and amplification, it scales higher than the rest, and is potentially the best lower-mid range product out there (assuming the neutral clean sound is what you are interested in). I’m finding it an indispensible tool to use while reviewing amps and DACs because it gives such a clear window into the sound, like a junior in-ear version of a Sennheiser HD800. When using a Sansa Clip I find the Westone and 1964 Ears models superior, but when used with an amp the Atom takes a clear lead.
 
From all the descriptions I’ve heard by people I trust, the Ultimate Ears Reference Monitor seems like it has a sound signature close to the Atom. I haven’t heard the UERM so I can’t confirm the similarities, but all the reviews I’ve read of that product basically sound like they are describing the Earproof model. I’m not implying that they are equals – the UERM has three drivers and sells for twice the price. Logic says it should be better (though I’m not exactly sure how much better) but I have no way of knowing until I hear the UE model for myself. But for someone interested in that type of sound yet finds the $1,000 price a bit steep, the Earproof Atom could be a good alternative.
 
CONCLUSION
I don’t see an update about the Atom on the Earproof website at this point. So I’m not really sure what the status is. But I hope this ends up being a commercial product that can be enjoyed by more people than just me, because it absolutely deserves to be heard. The sound is about as neutral and clean as I’ve heard from a custom IEM, yet it manages to keep me engaged rather than bored. The form factor is very comfortable, and the soft silicone ensures a perfect seal. It really is an excellent user experience all the way around.
 
The difficulty I see is that it doesn’t reach its full potential with a standard portable DAP or phone. Many people like to travel light, and you’d think these tiny customs would be perfectly matched with something like a Sansa Clip+. But using them in that fashion does not give you the full picture of what they are capable of. I’m not just talking about the last bit of refinement either – they actually sound boring and lifeless in many cases. But plug them in to a portable amp, or better yet a home system, and they really take flight. The result is something like what you’d get running a quality near-field studio monitor. It may not have a massive soundstage, and is obviously limited in low frequency output, but nonetheless can sound breathtaking with good recordings. If that sounds like what you are looking for in a custom IEM, I encourage you to contact Earproof about the Atom.

 

 
 
There’s been lots of talk over the past few years, on this forum and many others, concerning the Asus Xonar line of soundcards. The Xonar ST and STX have basically become the standards in terms of reasonably affordable, high quality soundcards for the PC. For just over $200, you can add good sound and vastly improve your audio capabilities in comparison to an onboard audio solution.
 
Some people wish to take things a bit further with a dedicated external DAC. In most cases this is accomplished by connecting to the computer through the USB interface. Though many options exist on the market, Asus recently joined the party with their Xonar Essence One standalone unit. At $600, the Essence One is a dedicated DAC with a built in headphone amp. It promises to raise the sound quality bar compared to its soundcard siblings. Reviews on HeadFi seem mixed, with some people really enjoying it and some being a bit disappointed. But I haven’t seen an in depth review done by someone I trust, so I can’t say for sure.
 
But this review is not about the Essence One. It’s about the Kao Audio UD2C-HP. Kao Audio is an audio company comprised of former Asus employees, all of whom are also music lovers. They left Asus in 2009 to launch a company dedicated to high end audio. The team is almost completely made up of engineers who worked in the notebook and motherboard R&D sections. My contact, Ting-Kuo Kao (referred to as just Kao from here on out) says he was in touch with the project manager of the Xonar team -  the PM would sometimes come to him for design advice, though his suggestions always ended up being too expensive to be implemented. Despite having severed ties with Asus (and now being “the competition”), Mr. Kao was never anything short of respectful when discussing his former employer.
 
The first product from Kao Audio is a standalone DAC/headphone amp called the UD2C-HP. It’s just coincidence that Asus came out with a similar product around this same timeframe. The similarities are only in function – these two units are completely different in design and execution, and I’d say that Asus and Kao have fundamentally different philosophies when it comes to audio reproduction. The Kao UD2C-HP is available worldwide via eBay, for the price of $988 shipped.  
 
 
 

 
 
DESIGN
First, let’s examine the name. The UD obviously stands for USB DAC, although the unit does also feature a coaxial SPDIF input. I’m assuming the 2C makes reference to the two separate DAC chips on board. The HP is for the integrated headphone amp (apparently there is a UD2C version which omits the headphone functionality). And there you have it.
 
Getting more specific: the UD2C-HP is a fairly compact device. It’s almost exactly the same size as the NuForce HDP in width and depth, but twice as thick. Though it does have a USB interface and could be considered “transportable” due to the small size, it requires power from the wall rather than drawing power from the USB connection. But used as an all in one unit, this device will comfortably fit in places that most other high quality solutions just won’t go.
 
In terms of features, the UD2C-HP won’t overwhelm, but what does have should be enough for most situations. You have the USB input which is limited to 16-bit/48kHz (more on this later) and the coaxial SPDIF input which can take anything up to 24/192. The RCA output stays at a fixed level, so this device does not act as a pre-amp. But there is a volume control which applies to the headphone output. To maintain the slick industrial look, this is handled by a touch sensitive pad on one corner of the device.
 
Internally, the unit takes a somewhat different approach. I say different in contrast to most of the higher quality DACs I’ve enjoyed lately, but it’s nothing too far-fetched. The focus here is on signal purity above all else – extremely short signal paths, overkill-quality parts (from the Schurter brand headphone socket to the high bandwidth relays to the premium RCA connectors), and a complete lack of what Kao feels to be unnecessary circuitry. That means no opamps (anywhere) and no upsampling, though the Delta-Sigma design of the twin DAC chips does use oversampling. The old audiophile adage of “simpler is better” absolutely comes in to play here.
 
Speaking of those twin DACs – rather than using a parallel design like some of the competition (see Cambridge DacMagic, Bryston BDA-1 for examples), the Kao unit dedicates one chip to the line out and one chip to the headphone section. This is relatively uncommon, but it is the same method used in the $4k Resonessence Labs Invicta, so it isn’t unheard of. The line out uses a Crystal CS4351 DAC, and the headphone gets a similar CS4350. Both units contain what Kao says are excellent I/V and filtering circuits integrated into the chips themselves. So when tapping the line out you are getting the pure 2Vrms single ended signal directly off the DAC chip itself with no further tampering. The CS4350 feeds a differential voltage output straight to the TI TPA6120A2 chip for headphone amplification. Kao feels that splitting the signal from a single DAC chip is a compromise, and I’ll cover that further in the interview portion of this review. Volume control for the headphone amp is done in the digital domain, using the onboard feature in the CS4350 along with an external MCU.
 
The supporting hardware is fairly simple: a TI PCM2704 converts USB signals to SPDIF before routing them to the tried and true CS8416, which also accepts SPDIF signals directly from the coaxial input. I asked Kao about his choice to not only use an adaptive mode USB interface, but one that is limited to 16/48 or less. He advised that it came down to two main reasons – 1) that the vast majority of music released is still in the Redbook format, and 2) that iPad compatibility through the Camera Connection Kit was a high priority. This lines up with my experience that DACs using 16/48 USB implementations have the least amount of issues with this playback method. So in what could be seen as a compromise, Kao made the choice to go with real world usability over an impressive spec sheet.
 
I have a few specs to point out. First is the power delivered from the headphone out: 1W at 32ohms and 85mW at 600ohms. They didn’t have measurements available for other impedance loads at the time, but I’ll update if that becomes available. It should be sufficient for driving most headphones short of difficult planars, but obviously is more powerful into the lower impedance range.
 
The second figure is with regards to jitter. Kao repeated what I’ve heard from other designers, which is that exact measurements into the low picosecond range are very difficult to obtain with any degree of confidence. He advised me that the device had measured very low, but didn’t want to put much faith in the specifics, so he asked me not to mention the number (it was quite low is all I can say). I don’t know much about the testing conditions or how this translates to real world use. Since the design seems optimized towards signal integrity, I have the impression that feeding a low jitter signal would get you excellent results, and feeding a poor quality signal would give poor results. There isn’t much in the way of jitter reduction except for what is built in to the DIR and DAC chips themselves, so the design instead relies on PCB optimization and power supply precision to keep jitter under control.
 

The textured finish is such that it is hard to photograph without capturing
blemishes and smudges. In reality, dust is more of an issue.
 

 

 

 

Touch pad for volume control - works quite well, very precise.
 
INTERVIEW
I did an interview style email exchange with Kao, but I don’t think it is fair to post it verbatim. His English skills are passable but it gets a bit confusing when we get into technical discussions. I also never specifically asked for permission to quote him so I’ll just paraphrase. My questions will be the ones in blue.
 
What are the goals of your design?
 
1) We want to recreate a detailed performance without adding anything. That means a flat frequency response. We want people to hear music as was intended by the one who created it, and not embellish that in any way.
 
2) Functionally, we want to be simple but effective. We don’t want people paying for things that they won’t use. But for the things that our product does do, we want it to do extremely well.
 
3) The external appearance of the product is very important to us. We want users to enjoy music as well as the environment around them. Nobody wants their listening area to look like a factory with unsightly equipment everywhere.
 
 
How did you reach those goals?
 
We did lots of measuring, but in the end it comes down to listening tests to determine what works and what doesn’t. Our collective experience as engineers helps with the measurement part, and our experience as music lovers helps with the listening part.
 
 
How do you feel USB sounds compared to SPDIF?
 
In most cases I prefer USB because it is more consistent. SPDIF is greatly affected by the quality of the input source. When fed by a very good source, the result can be excellent. But USB is more consistent.
 
 
Why did you choose these specific DAC chips?
 
The CS4350 and CS4351 are advanced multi-bit delta-sigma designs. While the top of the line CS4398 is technically the better chip, in our listening we preferred the “lower” models. Part of the issue is that the CS4398 is more complex, with more functions and thus higher load parameters. The CS4350/4351 is a perfect fit for our needs without any unnecessary extras, which is likely why it sounds better in our configuration.
 
 
Why does the headphone section need a separate DAC?
 
When splitting the signal from a single DAC chip, you lose some low level details due to trace bifurcation. We found this to be the case even when there is no load connected to one of the outputs. It has to do with signal reflections which can cause distortion. It is a small issue but still something we wanted to solve, to give the ultimate sound quality. It can be avoided by making the PCB traces longer, but this is also undesirable for obtaining the purest signal quality. The reason we don’t use a pair of identical DAC chips is that the CS4350 gives us the differential voltage output which we need for the headphone driver, and the CS4351 gives the single ended signal we need for the line out.
 
 
What other aspects of the DAC contribute to the overall experience?
 
We believe that to make the DAC convert digital signals into high quality analog signals, you not only need the best quality power in general, but it must also be suitable for every part of the circuit. For example, USB receiver circuit, headphone amplifier circuit, clock PLL circuit, etc. all have different operating frequencies, so the required power characteristics are different. We use high-frequency switching power supplies with medical and aerospace grade specifications. We carefully tune everything to ideal levels. This makes digital data unit, clock PLL unit, pure analog, and digital-analog circuits each get the most appropriate power.
 
A high-frequency switching power supply is still a switching power supply. Electronic switches and filters are used to generate power. But both types have different circuit designs. Output power quality is also very different. In general, when the modulation frequency is greater than 20kHz it can be classified as a high-frequency switching power supply. Our high-frequency switching power modulation frequency is approximately 100kHz. In audio equipment, there are only a few other companies using these types of power supplies, such as Chord and NuForce (with their higher end Reference products). This is because very few people understand noise control technology, especially when it is used in audio equipment.
 
 
CS8416 seems to have higher jitter at 48kHz and 96kHz than some of the alternatives. Can you explain why you chose that model instead of other options? It does seem to be one of the best for 192kHz sample rates, but that isn’t really your focus. Did you consider any other options from Texas Instruments or Wolfson?
 
We tried to use the Wolfson WM8805 and TI DIR9001. Only the CS8416 give us the required sound. Another reason – we are mainly concerned with 44.1kHz sound performance, because this is the most frequently used. At this sampling frequency, we believe that CS8416 is the best. We don’t want people to judge strictly from the numbers, and we hope nobody will think less of our product because it might not use the highest specification chips. We’ve spent much time comparing and would rather build something that we believe sounds better, instead of just seeming better on paper.
 
 
Do you have a favorite headphone to use with the headphone output?
 
Grado RS-1i and Denon AH-D5000 / AH-D7000. These are our favorites. But we feel that the UD2C-HP sounds great with a wide variety of headphones.
 

 

 
 
BUILD QUALITY
The UD2C-HP is a very unique device. At first glance it appears to be formed from a single block of aluminum, though closer inspection reveals an upper and lower half. This is the first DAC I’ve reviewed where I wasn’t able to open it up for a closer look – I was afraid that I wouldn’t be able to get it back together properly. So I relied on Kao to provide interior pictures.
 
I find the finish striking and components to be of very high quality. Great care was taken during the selection process of every part; for example, Kao says they tried over a dozen RCA connectors before settling on the current choice, which had as much to do with sound as it did with aesthetics and durability. The Schurter brand power toggle and headphone jack both feel great, adding those last satisfying details to the user experience.
 
The only downside I can find is that the unit shows debris very easily. It is the opposite of a fingerprint magnet – instead, it shows lint and dust. But this is easily remedied with a cloth such as the type normally used for cleaning sunglasses.
 

 

 

 

 
 
 
 
PACKAGE
Kao sends a generous helping of accessories along with the DAC. You get the unit itself, a short USB cable, a longer USB cable, a thick aftermarket style power cable (branded as “Monitor Acoustics”), and a leather base for the unit to sit on. The DAC itself does not have any sort of rubber “feet” or padding on the base, so this leather pad is used to keep from scuffing the table (or whatever the device is sitting on).
 
I discussed the power cable with Kao. He maintains that differences in impedance, resistance, and conductance can result in audible differences between cables. A well designed power cable can help you get the most from your device. That explains the massive cable included in the package. I’m not really big on aftermarket cables but I still appreciate the fact that Kao included something nice. I’ve seen many companies include a basic cable and then use it as an excuse when someone isn’t satisfied with the sound of their product – insinuating that the customer need only to supply a quality aftermarket power cable to start hearing what their product is really capable of.
 

 

 

 

Monitor Acoustics power cable
 

Leather pad for the base
 
 
EQUPIMENT
This is a list of associated equipment I used for evaluating the Kao UD2C-HP:
 
Source: Acer laptop running Windows 7 and Foobar2000, JF Digital HDM-03S music server, Pioneer Elite N-50 streaming audio player, iPad2 with USB Camera Connection Kit
 
Amplification: Analog Design Labs Svetlana 2, Violectric V200, Yulong A100, Matrix M-stage
 
Headphones: Heir Audio 8.A, Sennheiser HD700 prototype, Unique Melody Merlin, Earproof Atom, Audio Technica W1000x, Lawton Audio LA7000
 
Speaker setup: Parasound 2125 amp, Octet Matrix DE7 speakers
 
Cables used were by Signal Cable including the Analog Two interconnects and Digital Link coaxial cable, and I obviously used the Kao power and USB cables. Music was a mix of various genres, mostly stored in the FLAC format, from 16-bit/44.1kHz to 24-bit/192kHz. I burned in the DAC for well over 100 hours prior to doing any serious listening, and by now I’ve got probably 500+ hours on it.
 

Pictured stacked with the Squeezebox Touch, which is very close in size.
 
 
LISTENING
I’ll start by addressing the UD2C-HP as a DAC only. I wasn’t sure what to expect since the design is so different from the rest of my DACs. Would it sound ultra-analytical? Or smooth and rolled off like a NOS design? Thankfully it is neither of those – for such a tiny little unit, this DAC really delivers a big performance, while maintaining a nice balance between those two extremes.
 
The sound as a whole is very transparent and neutral. I’m not hearing any significant frequency deviations in the form of boosting or roll-off. More importantly, I don’t hear any glare in the highs; just crisp clean reproduction. We often associate “neutral” with “bright” or “boring”, but that isn’t the case here.
 
Vocals were a very strong point. Whether listening to a lovely “audiophile approved” voice like Diana Krall, or a lesser known songstress like JJ Heller, vocals came through with startling accuracy. I felt like I was in the room with them and could hear every vocal intonation, however slight. Yet it never felt forced like some DACs do when they strive for this type of accuracy.
 
Bass hit strong and deep but maintained full composure. Listening to “Super Double-Bass: The Artistry of Gary Carr”, a great sounding release in the JVC XRCD format, I heard excellent control and rock solid definition. This unit is definitely capable of accurately resolving low frequencies when it comes to real instruments. Switching to electronic music with heavier bass: from Skrillex to Mistabishi, The Crystal Method to Crystal Castles, the UD2C impressed with deep impact - but it fell a little short of some of my other DACs in this regard. I probably wouldn’t notice without direct A/B comparisons though.
 
Over time a pattern started to emerge – I think this DAC has some of the best tonal accuracy I have ever heard. It excels with reproducing the timbre of real instruments and voices. It just sounds utterly natural and convincing. Its soundstage is large enough, and more importantly, accurate enough, to sound realistic without calling attention to itself. At the same time it falls short of my reference units in some other areas - overall resolution, coherency, and the ability to handle complex passages without any congestion. Not that it is actually poor in these areas… by most standards it still does a great job. Just not compared to the absolute best out there (which of course cost quite a bit more money).
 
I hate saying a DAC is neutral and doesn’t have much sound of its own. That seems like such a generic review, and gives the impression that I didn’t bother to really figure out the sound of the device. But it actually seems to apply in this case: the Kao DAC doesn’t sweeten your music, it doesn’t soften edges on brittle recordings, it doesn’t deliver lush warmth - it just gets out of the way of the music (another term I despise) and lets it flow.
 
I do have to note that Kao was right on with his description of the USB input compared to the SPDIF input. Using USB with several different computers and playback programs, I consistently achieved what I consider very good sound. Despite the limitation to Redbook quality tracks, I heard some absolutely beautiful renditions of my favorite music. When I tried SPDIF, the results seemed more dependant on transport quality. My Pioneer Blu-Ray player, clearly not intended for high end audio, sounded inferior to USB when used as a transport. My Lexicon universal player, fairly expensive when new, sounded about equal to USB. And my low jitter JF Digital music server (basically a computer purpose built for quality audio) sounded even better than USB, but only slightly. Honestly, I would have thought that adaptive USB mode using the older PCM2704 transceiver would offer the worst performance. But that just wasn’t the case. So whatever Kao Audio is doing, it seems to be working. The only consistent benefit seen with SPDIF is the ability to play hi-res tracks.
 
Switching to the integrated headphone amplifier, I was met by largely the same transparent sound. After careful listening I determined that the amp section has a hint of flavor to it that seems absent from the line-out. It has what I’ve heard described as a “Japanese Hi-Fi” sound. Compared to something like my Violectric V200, the Kao amp section has a bit less extension at both ends of the frequency extreme. It seems to spotlight the mids just a little, enough to call attention to them but not in an overpowering way, nor enough to make the other aspects seem too recessed. It’s an enjoyable sound and I could see myself living with it as my only amp if I wasn’t such a HeadFi geek. It reminds me of a less refined version of the Blossom Blo-0299, which I thought was a very nice amp (though expensive at nearly $1500). They both have the same slightly mid-centric sound, a little on the “polite” side, but very enjoyable. I went back and forth between the built in amp and some stand-alone units of various prices, and I think this amp is very well matched with the DAC section: unless you are spending a good amount on a nice mid to higher end amp, you likely won’t need to upgrade.
 
Another good thing was that it was nice and quiet with sensitive IEMs, and had sufficient drive for most headphones. I don’t have any planar models in house at the moment so I can’t confirm how well it would do. But based on the power ratings and general sound signature, I’m guessing it would pair well with the LCD-2 and HE-500, if not being the last word in performance. The HE-6 is most certainly a no-go. I’m planning on trying the HE-400 soon so I’ll update, but I’m fairly certain that will be a good match.
 
I recall the stir caused by the TPA6120A2 when it first came out; some people hailed it as the ultimate headphone driver IC, and others scoffed at it, saying specs alone don’t make for good sound. I remember Kevin Gilmore saying in this old thread that the TPA6120A2 was “mighty good indeed” and that it sounded better than opamp/buffer solutions. The context there was for portable applications, but I’d argue that Kao is working with space restraints closer to portable amps than desktop solutions. Like the DAC section, I really do think the output quality is tied to the supporting circuitry, especially the power supply. That’s why Kao can extract such excellent performance without using exotic parts.
 
 
COMPARISON
I recently reviewed the Yulong Sabre D18 DAC, which sports the ESS ES9018 Sabre Reference DAC. I praised it for its ultra smooth, musical tone, and said that nothing I’ve heard really came close for the price ($699). Given the similarities in price and the fact that I’ve spent so much time with the D18 recently, it will be my comparison.
 
The Kao UD2C-HP is a very different sounding DAC, both in terms of features and sound. It is single ended, USB oriented, and has a built in headphone section, all of which are opposite of the D18. Sonically, the two are rather different as well. The Kao has a more neutral presentation, without the warmth and smoothness of the D18. The Sabre unit has the edge in soundstage size/accuracy as well as low frequency extension. The UD2C counters with better perceived detail retrieval and that amazing tonal accuracy. Deciding which one sounds better will ultimately come down to the system it is matched with.
 
To put it in headphone terms, the D18 is the equivalent to an Audeze LCD-2 R1, while the UD2-C is more like entry level Stax. One is all about rhythm and drive, with a thick, bold sound that is relatively forgiving of flaws. The other is more of a neutral transparent presentation that really nails the timbre and speed of the music. Neither is perfect, but both are quite good, and will appeal to different audiences. The D18 is cheaper but the UD2C-HP has a nice integrated headphone amp, so it roughly evens out. With gear this good, there are no losers in the comparison.
 
 
CONCLUSION
It’s hard not to stack this Kao Audio DAC up against the new release from former employer Asustek. Yet the Kao Audio UD2C-HP and the Asus Xonar Essence One are about as different as they could possibly be. The Asus boasts an eleven opamp design while the Kao is completely free of opamps. The Asus has a linear power supply with a toroidal transformer while the Kao uses a high speed switching power supply. The Asus has a hi-res asynchronous USB implementation while the Kao sticks to 16-bit/48kHz for maximum compatibility. The Asus uses upsampling while the Kao processes signals at their native rate. Obviously each company is approaching the problem from a different angle, which is why their solutions look so different. Unfortunately I can not draw any conclusions due to not having heard the Essence One for myself. I’ll work on getting one and update if I can.
 
Asus aside, the Kao DAC is a very unique and impressive device. With a “less is more” approach, it certainly looks different than most $1,000 DACs, on the inside as well as the outside. But the sound easily justifies its position in that price bracket. It goes to show that even “basic” DAC chips can sound phenomenal when surrounded with the right environment. I really do think that the advanced power supply is key to their accomplishment though I’m sure there are other factors involved. I find their approach refreshing – while it seems like everyone is jumping on the latest features, Kao Audio dares to be different. Not just for the sake of being different, but to reach the goals they set: small size, attractive design, emphasis on iPad compatibility, and a purist approach to sound reproduction. I appreciate this specialist mentality – it seems like they are trying to please a specific type of customer rather than casting a wide net.
 
I’m using the UD2C-HP in a bedside rig. Signal comes from my iPad2 with Home Sharing, streaming content from my desktop in the other room. Headphones are the Lawton LA7000, Ultrasone Edition 8 and Heir Audio 8.A, among others. It takes up very little room, looks fantastic, and most importantly, sounds great. None of my other gear could take its place without some compromise in size, sound, appearance, or cost. With that being the case, Kao has obviously accomplished exactly what they set out to do.
 
 
 
 
 
 
 
 
 

 

 
 
Just adding a quick summary based on my time with the prototype version of the HD700. In my opinion this is a very good headphone, yet I know it won't be perfect for everybody. But no headphone ever is!
 
It basically takes the HD800 sound, reduces the treble energy to some degree, and possibly bumps up the bass impact a tad. Either that or it just seems that way due to the treble balance. Since mine was a prototype version, there is a chance that the final sound will change. Therefore I'll be speaking in generalities. I know for sure that there will be updates to the headband to offer more padding. Despite that, I already found the HD700 to be supremely comfortable. Maybe it is just my head being the perfect size for them, but I think these are the most comfy headphones I've ever worn. Revised padding shouldn't change that, and if anything will make it even better.
 
Sound:
 
As mentioned above, these have a similar overall tone to the HD800. If you despised the HD800 then the HD700 probably won't win you back. But for some people this might be perfect. Maybe you loved the HD800 but couldn't afford it. Or maybe you could afford the HD800 alone but not the quality amplification it requires. Or maybe you loved the HD800 clarity and soundstage but couldn't quite get over the lightness of the bass in relation to the treble. The HD700 addresses all of those issues to some degree:
 

1. At $999, it isn't cheap, but still quite a bit less than the $1500 HD800
2. It seems significantly easier to drive. Not only that, but it seems less "picky" about amplification, pairing fairly well with almost anything I threw at it. This might be partially due to the less tipped-up sound signature in general. 
3. It has a somewhat more "mainstream" ratio of bass to treble. By that I mean the treble is shelved down by a noticeable amount (though still prominent - this is no HD650). So while the best sound still comes by way of Diana Krall style "audiophile" tracks, you can comfortably play some Steve Miller Band and not feel like the bass is too shy. I know that many people find the HD800 perfect in this regard - but we have to recognize that many others do not. 

 
Is this headphone actually better than the HD800? Not exactly. The HD800 still has superior imaging and soundstage, though the HD700 comes rather close. The HD800 still has better details. And on the proper rig, I think the HD800 is just a more transparent window into the music. But the HD700 comes close in many ways, and doesn't take as much to get there in terms of source and amplification. I think it could be a better match for more people and more systems.
 
It isn't the perfect headphone. There is an issue with sibilance in some tracks. In other cases the highs can be peaky and sharp. The plastic construction, while extremely light weight and comfortable, will be fundamentally disappointing to some users. And in the end some folks will still find them too bass light. There is strong competition from planar models like the HE-500 and LCD-2, though in my opinion the HD700 is roughly as good as those (though obviously different). The HE-500 manages to undercut the HD700 by $300, which can't be ignored.
 
Take all this discussion with a huge grain of salt - these are not yet finalized, and could have some significant changes before they come to market in a few months. A big determining factor will be the manner in which Sennheiser handles their sales: if retailers are forced to strictly enforce the MSRP, I believe there will be less interest. But if the "street price" drops to around $800-something I believe they will become extremely popular. Either way I believe HeadFi will be buzzing about the HD700, for better or worse, for some time.
 
And now some eye candy:
 

 

 

 

 

 
 
 
 
 
 

 
 

 
 
 
 
When it comes to DACs, many people have the misconception that the actual chip used for D/A conversion is the only thing that really matters. That makes about as much sense as saying the drivers in a speaker are all-important, and the crossover/enclosure don’t matter much. When we put it in those terms it sounds like nonsense. Yet this thinking persists in the realm of D/A conversion. Experience has shown that you can have an excellent sounding DAC using a fairly basic DAC chip. Likewise, you can have a DAC that sounds unimpressive, even though it may use the latest/greatest chip (or even several of those chips). The total overall design is much more important than each individual piece.
 
With that being established, I do have to acknowledge what seems to be a superior DAC chip compared to many others on the market. Unless you are out of the loop, you have likely heard of the ES9018 Sabre Reference, the top DAC chip from ESS Technologies. Call it coincidence, but I notice that a very high number of products using this chip have gone on to become extremely well regarded. Examples: Wyred 4 Sound DAC 1/DAC 2, Eastern Electric MiniMax, and Weiss DAC202. In my personal experience, the Anedio D1 and Resonessence Labs Invicta are two of the best DACs I’ve experienced regardless of price, and both use the ES9018. Again, I certainly don’t think the chip itself is the onlycomponent involved in making these sound great. But it may allow them to reach a higher level than they otherwise could if they used a competing chip from Wolfson, Texas Instruments, etc. This is just an observation and I won’t pretend it is the only school of thought.
 
So we’ve got a high-tech new DAC chip, which appears in various highly-regarded DACs. Just choose one and you’re all set, correct? Unfortunately, nothing in audio is universal. Some people have complained that the “Sabre sound” can be too analytical, perhaps sounding a little off in the upper mids/highs. For that reason, some people have stayed away from the ES9018 based models. This especially applies to folks who love the stereotypically smooth “tube sound”. I don’t personally have this issue but there are many Sabre based DACs I have yet to hear.
 
This brings me to the topic of this review: the Yulong Audio Sabre D18 DAC. This is the first Sabre based DAC from Yulong, and they must have liked the ESS chip so much that they included “Sabre” in the name. This is by far the most ambitious and expensive design that Yulong has yet to produce under their own brand (they also do OEM work so they may have built higher end gear for other companies, I don’t know). This was meant as an all out statement product, while keeping a fairly low price – at $699 it is the most affordable DAC on the market which uses the ES9018, by a considerable margin.
 
I’ve reviewed several of the prior designs from Yulong in the past, including the D100 and U100 DACs and the A100 headphone amp. All have impressed me at their price points and even beyond. So I was curious how the flagship D18 would stack up against some of my favorite DACs. I’m happy to say that it holds up well – while not beating my reference units, the D18 brings something unique to the table that I have not yet heard from an ES9018 design.
 
 
DESIGN
The D18 is a fairly compact unit, using what initially appears to be an upgraded version of the D100/A100 enclosure, but is actually a completely new design. As such it should be able to fit into nearly any system: it won’t look too big next to a small headphone amp, nor will it look too small next to a full size amp. Weight is listed as just over 5 pounds but subjectively feels like more than that.
 
The main focus here is minimalism – the front panel has a power button and a source selection knob, and that’s it. The rear panel features RCA and XLR outputs, and an array of three inputs – coaxial, toslink, and AES/EBU. That’s right, no USB input. Apparently Yulong (the designer) feels that since there is already a plethora of competent USB to SPDIF converters on the market at reasonable prices, there is no need for him to reinvent the wheel. Those that need USB can choose from one of the many devices out there, while those that don’t are freed from paying extra for a function they won’t use. Obviously this will be somewhat of a polarizing choice – some will find it refreshing, others absurd. I do recognize that it is strange to see a “flagship” digital product without USB in the year 2012. On the other hand, the $699 price leaves plenty of room in the budget for a USB to SPDIF converter, while still coming in at less than most competing Sabre based units. Besides, this strategy isn’t unheard of - the well regarded Metrum Octave does the same, and Schiit Audio offers their Bifrost sans USB for a savings of $100.
 
Internally, the D18 bears a vague resemblance to the D100 in terms of general layout. Both use the same toroidal power transformer from Canadian firm Plitron. Both have a similar size PCB, and I see some shared components like the cable and fuse harware. Aside from those, the D18 appears to be improved in every area - better regulation and stabilization in the power supply, superior design and components in the output stage, higher quality system clock, and more advanced overall layout. And let’s not forget the ES9018 DAC, a ~$60 chip as compared to the ~$7 AD1955 used in the D100. Again, the chip (and the price) won’t tell the whole story, but it is worth mentioning.
 
The D18 is supposedly capable of accepting 24-bit/192kHz signals on all 3 inputs. I say “supposedly” because my reference gear tops out at 24/192 over coaxial or AES/EBU, and 24/96 over toslink. I suspect that the limitation of 96kHz over toslink is irrelevant since very few devices (if any) can actually achieve the theoretical maximum of 192kHz. The main point is that the D18 will accept basically any stereo signal you can throw at it short of DSD audio, which is only supported by a handful of devices. The ES9018 is actually capable of handling up to 32-bit/500kHz signals, but the SPDIF standards do not allow anything higher than 24/192. While some companies are using USB to handle higher rates, there isn’t really much point since the vast majority of music is 24/96 or lower, with the bulk of it being “lowly” 16/44.1.
 
The output circuit uses a pair of Analog Devices AD8620 opamps for I/V conversion, and a pair of AD797 opamps for low-pass filtering. I’m told the output stage appears very similar to the IVY module from Twisted Pear Audio, but I have no experience with that so I can’t confirm. In any case, it is far more elaborate than Yulong’s own D100. I’ll let the pictures tell the rest of the story. One novel feature that you may notice is something looking like a cable, connecting one area of the PCB to another. This is called an SMA interface, and it is used as a bridge between the input section and the ES9018 DAC. While it would normally be carried along through the PCB, Yulong says the SMA method does a better job of keeping this critical signal isolated from noise and interference. Once delivered to the DAC, things proceed in a more traditional manner. Note the custom made low phase noise crystal oscillator parked directly adjacent to the ES9018.
 

 
 

Plitron transformer
 

SMA interface
 

ESS 9018 and system clock
 

Analog output stage
 
 
INTERVIEW
Since Grant Fidelity is now the exclusive North American distributor of Yulong products, I asked them to assist me in getting some information. I don’t speak any Chinese, so Rachel at Grant Fidelity was very helpful. What follows is her translation of the questions and answers, with some editing for clarity.
 
[size=8pt]1) Can you explain the why the RCA outputs sound slightly different than the XLR? Is that something you went for on purpose, or did it just happen that way?[/size]
 
[size=8pt]A: The RCA and XLR output sound difference is designed on purpose to cater different headphones and music styles. It is also for better matching with the coming Yulong Sabre A18 headphone amp. [/size]
 
 
[size=8pt]2) Can you give rough jitter estimates? I know everyone measures differently, but some idea would be good to have.[/size]
 
[size=8pt]A: With 1KHz signal, Yulong Sabre D-18 has jitter measurement better than 1ps RMS. Sabre D-18 uses very high end reference clocking at phase noise -130dB. We consider the measurement to be outstanding even by high end standards. [/size]
 
 
[size=8pt]3) Can you talk about the matching A18 headphone amp - any comments on the design or release date?[/size]
[size=8pt]4) What "sound" were you going for with the D18, and do you feel you achieved it?[/size]
 
[size=8pt]A: Yulong Sabre A18 is a high end Class A headphone amp with K170/J74 JFET input stage. We consider JFET circuits to have better sound quality than vacuum tube circuits for input stages, and it will deliver rich smooth sound. The unit has low total harmonic distortion and wide frequency response. It comes with RCA and XLR inputs (real fully balanced circuit design) so that you can match it with other components. It is designed as a perfect match to Sabre D18 to show you the absolute full potential of what the Sabre D18 can achieve. I designed the Sabre A-18 for my pursuit of high end sound quality as an audiophile - in the design process, no cost objection was considered. I was after a rich, deep, smooth, detailed and dynamic sound and I personally think that A18 has achieved my design goal. It has low output impedance, sounds very musical, and matches well with a majority of headphones on the market. Launch time should be next 3-6 weeks, please check with our North American agent Grant Fidelity for official exact launch date. [/size]
 
[size=8pt]I cannot give more specific description of the Sabre A18/D18 sound. Listening is a subjective matter and people may have different opinions on how to interpret the sound they have heard. I will leave it to customers to provide their own description and unbiased feedback. [/size]
 
[size=8pt]5) Was there any area where you had to "cut corners" with the D18 in order to keep the price low? Or is this a true statement product with nothing held back?[/size]
 
[size=8pt]A: I wouldn't say 'cut corners' but in production we need to have an overall cost control in order to provide the final product at a suitable price. Keep in mind that production cost in China is much lower than in western countries and our worldwide universal retail price also means much less mark-up in the pricing structure. People in USA or Europe are paying the same price as if you personally come to China to buy from a dealer here. Sabre D18 and Sabre A18 are both of very high end sound but at much less price point compared to their American or European counterparts. I personally refer to this as 'value' - we provide high 'value' products - not just high end or high price. It's the ratio of price vs. quality that matters in the end to consumers. So itis our statement product with nothing held back in design, but our production/distribution model is ultra lean and efficient. The buyer's money has been most effectively spent on sound, not on reselling cost.[/size]
 
 
[size=8pt]6) Did you find the ES9018 difficult to work with? I've heard that from some designers.[/size]
 
[size=8pt]A: ES9018 is quite different from any other DAC chip on the market so there is a learning curve involved for best utilizing the chip in a final product. We spent substantial time to develop the Sabre D-18. We are planning to develop more products with the ES9018 chip down the road.[/size]
 
 
I’m not sure exactly what to make of the 1ps RMS jitter measurement. I know that CEntrance makes the same claim with their DACmini products, but I’m not sure either company is testing as thoroughly as the folks at Audiophilleo or Anedio. Both of those teams have extensive measurements available for the end user, and both have mentioned how difficult it is to get an accurate number when you are dealing with such low levels. In any case I think it is still safe to say that the D18 does an excellent job, and even if they are off by a factor of 10 it would still be a very good result.
 
Also worth checking out is THIS post on the Grant Fidelity website. It documents their trip to Yulong headquarters and shows some pictures of Yulong’s work area. This guy is clearly “one of us”, owning the Sennheiser HD800 and beyerdynamic T1 among many others. He is also clearly serious about establishing his company based on quality rather than price alone. He is very heavily invested in measurement equipment, and would rather the company grow slowly in size and reputation rather than compromising to speed up the process.
 
 
 
BUILD QUALITY
The D18 uses a nice thick aluminum material for the enclosure. Again, see the pictures – it’s thicker than the D100/A100 units. The source selection knob feels like solid aluminum too, and doesn’t come off without removing a screw, thus addressing a complaint some people had about the D100. It moves with a very reassuring “click” from one input to the next, and a corresponding LED lets you know at a glance which source is selected. Even the front panel power button has a confident feel to it when pressed. Overall it feels more like a flagship product than the D100 did (though the D100 was pretty nice as well).
 
 

 
 

 
 

 
 

 
 

 
 
 
PACKAGE
The D18 comes in the usual Yulong packaging. It’s efficient if not particularly extravagant, and should keep the item protected well enough during its journey overseas. There really isn’t anything to this device that would need explaining in the manual, so they throw in some measurement printouts.
 
 
EQUIPMENT
This is the associated equipment I used to evaluate the D18.
 
Source: Lexicon RT20 universal disc player, JF Digital HDM-03S digital audio server, NAD C 446 network audio player
 
Amplification: Violectric V200, Analog Design Labs Svetlana 2, Yulong A100, Matrix M-Stage
 
Headphones: Heir Audio 8.A, Unique Melody Merlin, Lawton Audio LA7000, Sennheiser HD700 prototype, Earproof Atom, Ultrasone Edition 8, Audio Technica W1000x
 
Cabling was by Signal Cable, music played ranged from CDs and 16/44.1 FLAC files all the way up to 24/192 releases. I let the D18 burn in for over a week solid prior to doing any listening (not that I think it is required but I was busy).
 
 

This is not my picture, but someone on Erji.net has both the D18 and the
Weiss DAC202, and says the D18 is a very good product. The intricacies
of the comparison were lost in translation.
 

Some of my listening and comparison gear
 
 
LISTENING
The Yulong D18 is an excellent sounding DAC. Nothing stood out to me upon first listen, which I take as a good thing – if I notice a gimmick like spotlit highs or artificially large soundstage, I might be impressed the first hour, but that sort of thing is sure to get old in the long term. So in my opinion all high quality DACs should sound very similarly excellent in general. Once you get into some heavy listening, you’ll start to discover the intricacies that make each one unique, but I don’t feel the comparison to be as easy as some people make it out to be.
 
First off, the D18 is on a high enough level that it doesn’t really require a step by step breakdown of lows, mids, highs, etc. As befitting a truly “high-end” device (in performance rather than price) it handles everything very well. Bass drums go staggeringly deep, brass has the proper bite, vocals are clear and lifelike. I would expect nothing less than this considering the fact that the lower priced D100 pretty much already had these things nailed. So in the spirit of making my reviews more readable, I’m going to assume that the reader has heard a top class DAC at some point in the past, and knows how it goes once you climb the ladder high enough.
 
Getting into those intricacies that I mentioned earlier – the character of the D18 is best captured by the word “smooth”. This is absolutely a DAC designed for musical enjoyment rather than sonic analysis. It gives the perception of warmth in the mids that deviates from the more clinical D100 sound, though I doubt it is the sort of thing that would come out in a frequency response measurement. There’s just some more energy there, giving a measure of extra weight or authority to the sound. But it never goes too far by sounding overly thick or slow.
 
 The smoothness also extends to the highs – it brings to mind the difference between a stereotypical solid state amp, compared to the stereotypical tube amp. The tube sound is not necessarily any darker or more rolled off, but still manages to take some of the edge off, facilitating long listening sessions and an overall lack of listener fatigue. Despite this smoothness, I feel that the D18 is still a very detailed DAC. There’s nothing missing per se – it just sounds a little smoother, a little cleaner than it might with something like a Benchmark DAC-1. Add in the wonderfully creamy mids and the prodigious low frequency response, and I can see how this DAC could be described as being on the warm/dark side. I’m not willing to call it dark, or at least not in the same sense that some headphones are dark, but I will concede to calling it warm. Once again - I certainly don’t mean to imply that there are missing details here; the DAC is very precise overall and extracts high levels of musical information. But it has a tendency to make things sound a little better than they really should. It’s not exactly forgiving in the true sense of the word: mp3 files and poor recordings will still show their warts. But it does give some flaws the benefit of the doubt, where something like the Benchmark unit would have no tolerance whatsoever.
 
Another excellent attribute of the D18 is the ease with which it serves up the music. It feels like everything just flows in an organic manner. Instead of lows/mids/highs you have a singularly cohesive experience from top to bottom, with no separation. Yet if you want to focus on any single aspect, you certainly can. Note that this is different from the idea of “instrument separation”. Though falling just short of my reference units, the D18 does allow for easy tracking of each individual performer, in a way that few (if any) sub-$1k DACs can match.
 
One interesting feature that could be considered a quirk or a benefit depending on your point of view: the D18 has a different sound when using RCA outputs instead of XLR. This being a true balanced DAC, the single ended output is generated from the balanced signal rather than the other way around like many other designs. As Yulong mentioned, he wanted to give people options, especially those who will be pairing their D18 with the upcoming flagship A18 headphone amp. Since that amp has both XLR and RCA inputs and both single ended and balanced headphone outs, it would be like having two different sounds in one setup. As far as the D18 goes – the RCA output seems to me like it has more of the traditional ES9018 “Hi-Fi” type sound. It’s still smoother on top than most, but lacks some of the warmth and body that balanced mode brings. Using the XLR output gives that really analog type feel, which is what I used most during this review. But don’t misunderstand – the RCA outputs still sound excellent, and with the right amp may actually be more appropriate than the XLR option. Keep in mind that you can easily use an XLR to RCA cable to extract the balanced flavor from this DAC, even if your amp is limited to RCA inputs. Also keep in mind that many amps will have differences of their own when using RCA inputs versus XLR – so it really comes down to mixing and matching to find the best synergy. The overall character of the DAC remains, so don’t expect night and day differences. But there is enough to give you some variety.
 
 

An early version of the D18 and matching A18 amp
 
COMPARISONS
 
Yulong D100
The D100 is an excellent DAC in my opinion. It is clean, transparent, detailed, and very representative of the skill Yulong has as a designer. I still gladly recommend it for people who want a great buy in the sub-$500 price range. It’s hard to talk about the superiority of the D18 without making it seem like the D100 is deficient, which is simply not the case. The fact that the D18 is superior in many ways does not take away from the accomplishment of the D100.
 
One of the biggest improvements offered by the D18 is the immersive, three dimensional soundstage. The D100 was certainly no slouch in that area, but the D18 takes it to that next level where only a small number of DACs can go. It was a modest gain when using most headphones, but when I tried a model with excellent soundstage performance such as the HD800 or the UM Merlin, I could discern a notable improvement. I heard similar improvement when listening through a speaker rig. There is just more “space” in the performance, both in terms of size as well as capturing the acoustics of the performance venue. When playing very good recordings from Mapleshade, Reference Recordings, MA Recordings, and other top notch labels, the D18 transports you “there” to a higher degree than the D100.
 
The other big difference is with how the top end is handled. Some people have found the D100 to be a bit bright when paired with certain gear. The D18 will not have that issue. It presents similar levels of detail, but in a completely smooth and effortless way. Is the D100 more accurate? Maybe sometimes it is, depending on your definition of the word. Is accuracy defined as reproducing the recording exactly, flaws and all? Or does it mean making a sound that seems lifelike, the way a real instrument is likely to sound, even if the recording may not reflect that exactly? Whatever your take on it, I suspect that the D100 would probably make for a better tool in a home studio situation, where you really want to hear those flaws. The D18 would be a better match for most “audiophile” type listening scenarios, where the listener is more concerned with making their music sound as enjoyable as possible. On the whole I do think the D18 is very much the superior machine and easily justifies the price increase.
 
Matrix Quattro
I have to preface this comparison by saying that I don’t have the Quattro DAC at present – I sent it around to some HeadFi members for audition, and it’s still making the rounds. But based on my listening notes and recollection, these are very different sounding DACs.
 
The Quattro is significantly more lit up in the upper mids and highs. Its hardware is very similar to the Benchmark DAC-1 and the sound generally reflects that, so the D18 has a completely different take on things. The strong points of the Quattro come close to matching the D18 – soundstage is nearly as wide, though a bit less convincing, details come through very clearly, and low frequencies are well done if not quite as controlled. The mids are leaner and the highs seem to be more grainy, though only in context of being compared to a nicer DAC. The bottom line for me is that the D18, though identically priced at $699, is indeed the nicer sounding DAC. There’s a catch though – the D18 doesn’t have nearly the functionality that the Quattro does. The Matrix unit offers the same three inputs as the D18, and gives the same choice of single ended or balanced output. While the D18 stops there, the Matrix offers a hi-res USB input, a respectable integrated headphone amp, an analog input, volume control for pre-amp functionality, and a remote control. So while the D18 is strictly a high-end DAC for non-USB sources, the Quattro is a multi-function all in one DAC/pre-amp/headphone amp. And it sounds pretty good too, competing well with the Yulong D100. So the two devices have very different target markets.
 
Anedio D1
The Anedio D1 is my reference unit, and in my experience has only been surpassed by the much more expensive Resonessence Labs Invicta. It is soon to be replaced by the updated D2 model (which I will be getting when it is released), but for now the D1 is the DAC to beat as far as I’m concerned.
 
At $1270, the D1 is nearly double the price of the D18. But they both share the same ES9018 at their core, so I figure it is a good comparison. The D1 has more features like USB in, an excellent headphone amp, remote control, and pre-amp functionality. But the D18 has advantages of it own – AES/EBU input and balanced XLR outputs.
 
Soundwise, these two share many similarities but also diverge in overall character. I’ll say right now that the D1 is still in a higher class – but that doesn’t surprise me, since the D1 is one of the best DACs I’ve ever heard at any price. The D18 is impressive in that it can approach the performance of the Anedio in some ways, for a significantly smaller investment.
 
The similarities are found in the ability of both units to convey inner detail. Both are spectacularly good in this regard. Both also have an excellent command of the presentation: whether the track is a solo vocalist or a complex orchestra piece, both units handle the performance with ease, allowing the listener to easily focus on whichever individual aspect they want (or just enjoy the presentation as a whole).
 
The differences: the D1 is a more linear presentation from top to bottom, with the main deviation being notable in the highs. Using RCA or XLR out of the D18, it always seems more smoothed out on top, with a subtle masking of imperfections. At times this is a desirable effect – many of my favorite albums are low budget, relatively poor recordings. Other times it is deleterious – the D1 takes good recordings, especially hi-res stuff, to higher levels.
 
Obviously the DAC is not the only contributor to the final sound, and you need to consider the entire chain including the headphones. If I want to listen to an album I enjoy, but that I know isn’t the best recording out there, I often reach for my setup consisting of the D18, an Analog Design Labs tube amp, and something like the Kenwood KH-K1000. This is a highly resolving yet musically satisfying setup that maybe isn’t the last word in technical ability but just hits my ear the right way. Examples would be when playing a Telarc release like “Some of my Best Friends Are… The Trumpet Players” by The Ray Brown Trio. Plugging the fairly smooth Kenwoods straight into the excellent D1 headphone amp, the result is still very much on the bright side. That’s not the fault of the Anedio; it’s simply there on the disc. But I might not necessarily be in the mood to deal with that for long term listening. Another example is the self titled release from Sister Sparrow and the Dirty Birds. I love the music, but the recording has a sort of dry, closed up feel to it, which is the exact opposite of the vibe you get when seeing them perform live. The D18/AD Labs/K1000 combo injects a welcome amount of warmth and life to the presentation; it still doesn’t capture the scale and energy of the live performance, but it engages the listener more than something like the Anedio/HD800 combo would. Again it comes back to the question of which version “accuracy” you are chasing.
 
 
CONCLUSION
I’ve said multiple times that the source is not the best place for any type of coloration, however small it may be. And I stand by that. If you have the choice, your best bet is to get an utterly transparent and neutral DAC. Can you find something which has the resolution, dynamics, soundstage precision, and sheer grace of the D18, for anywhere close to the $699 asking price? In my experience the answer is no.
 
I applaud Yulong, both the man himself and the company in general, for bringing the D18 to market. It would have likely been easier to make a fairly neutral device that built on the foundation set by the D100, and I bet it would have sold well enough. But instead they found what appeared to be an empty spot in the market, and filled it. I’ve long heard people complain about Sabre-based DACs sounding really great in most aspects, yet being somewhat lacking in musicality. I believe the D18 may be the perfect answer for those folks. In many ways it offers reference level quality, yet at times it departs from that in the interest of listenability.
 
The D18 will obviously not be for everyone. The person who uses something like a Benchmark DAC with a Gilmore GS-1 and HD-800, and wants to upgrade their DAC while maintaining a similar overall sound, should probably not be looking at the D18 to achieve that goal. The person who prefers a “tube sound”, likes vinyl, or just has a hard time enjoying the hyper-detailed sound that many of the best DACs provide, should absolutely give the D18 a try. Grant Fidelity offers a 30-day in home trial, so it would merely cost the price of return shipping to try the unit in your system. I suspect in many cases that return shipping would not be necessary.
 

 
TEAC WAP-8600
 
 

 
 
I’d like to thank Teac for loaning me this review unit. I can’t find a local seller that carries this model, but the price on Amazon.de is roughly €400, which currently translates to around $500 USD.
 
BACKGROUND
Younger readers might not know this, but Teac has some serious audio pedigree. Founded in Tokyo circa 1953, the company became well known in the 1960s for their expertise in audio tapes (reel-to-reel and later cassettes). For the next 40+ years Teac continued to have a big impact on the audio world – they started the Tascam pro-audio division, which basically created the entire concept of the “home studio”. They also launched Esoteric Audio, which for over 20 years has been on the cutting edge of high-end audio. I don’t blame people for thinking of them as primarily a company that made floppy disk drives, but there is actually quite a rich history there if you only look.
 
OTHER MODELS
Teac doesn’t seem to market heavily in the USA for their “Teac” branded audio gear. Esoteric of course gets plenty of exposure in the audiophile press, and Tascam is still a big player, but the rest of it is practically non-existent. The website for the consumer electronics branch shows a collection of CD players in a wide variety of styles and focus. There certainly doesn’t appear to be a guiding principal of design theme for much of it, and it can be hard to tell how one model compares to the rest.
 
An exception is with the Teac Reference line. We see a definite family resemblance between them, with a clear split in personality between the solid black models of the past year or so and the latest silver offerings. The older black models had received favorable reviews in The Absolute Sound as well as at 6Moons.com, so maybe Teac is showing renewed interest in expanding their audio division presence in the USA.
 
As far as streaming playback goes, you won’t find much on the USA website. Head over to the European site and you’ll find half a dozen choices, including the WAP-8600 which I’m reviewing here. This seems to be the top of the WAP line, with the others being variations of the same thing but with less features. There are other models that look interesting, such as the portable WAP-R8900 with built in speaker, or the WAP-AX100 and siblings which have built in ICEpower amplification. None of those meet the specific requirements that I’ve set as my focus for this particular series of reviews. There’s also the slick looking Reference 01 series which, though not qualifying for this specific article, looks very intriguing for HeadFi purposes in general. Further investigation may follow.
 
DESIGN
The WAP-8600 has two main components – the receiver unit and the control unit. The receiver appears to be similar across the WAP line, with other models having different remotes or lacking wireless connectivity. Teac also sells additional receivers which can be used as part of a multi-room system, all running from the same controller.
 
The receiver could easily be confused with a standard wireless router: it’s a small black box with a Wi-Fi antenna and an array of cryptic blinking lights. Closer inspection reveals the differences though – a 1/8^th inch headphone jack, Toslink digital output, RCA analog output, and several USB ports.
 
The controller consists of a charging base and the actual remote itself. The base holds the remote in such a way that it is tilted for easy viewing. The remote itself is based around a 3.5 inch touchscreen display with just a few hardware buttons on top.
 
I tried to open the receiver unit to get a peek at the innards. It should have been as easy as removing 4 screws on the bottom panel and taking the device apart. Unfortunately one of the screws has a special star pattern instead of a normal Philips head, no doubt to deter curious people like myself from messing around with the guts. This temporary setback would have been easily overcome if not for the fact that I have the unit on loan from Teac… so I don’t want to risk damaging it. For that reason, I don’t have specifics about the internal layout or specific parts used. With 3 of the 4 screws removed, I was able to move the cover just enough to make an opening and peek inside. While the outside of this unit might scream “router”, the inside looks decidedly “soundcard”. I see a bunch of purplish capacitors sprinkled liberally throughout, but I can’t read the brand. I also can’t tell what chips are used for the DAC or opamps. The manual lists signal-to-noise ratio as 95dB, which is something you might find on an entry-level CD player (the $349 Cambridge Topaz CD10 is listed as having the same SNR, though to be fair some of the Denon and NAD models are considerably higher). It’s a far cry from the 120+ range found in my reference equipment. Still, one vague number is not much to go by.
 

 

 

 
 
BUILD QUALITY
The receiver portion of the 8600 is simple plastic that isn’t much to look at. As I said, it’s just like a router, complete with wall-wart power. The good part is that it is small enough to fit in the places where routers often go – on top of a bookshelf, under a desk, behind a stack of other gear. The only reason you might need access to it is for inserting a USB drive or using it with headphones.
 
The controller, powered by an identical wall-wart PSU, looks a bit more upscale than the receiver. Notice I used the word “looks”. Where the remote appears to have metal trim, it is really just painted plastic. The rest of it is a sort of textured plastic that has a bit of a non-slip coating. It works well enough but still feels somewhat cheap. The rear battery cover on my unit seems especially flimsy. On the plus side, the remote unit slides into the charging base very nicely (unlike my old Logitech Harmony 880 remote which I’m still upset about). I like how the charger positions the screen at a laid back angle so you can use it without needing to take it out.
 
One negative thing that I can’t avoid mentioning: the controller uses a resistive touchscreen rather than capacitive. In case you are too young to remember resistive touchscreen technology – it was commonly used in early smartphones from HTC and others. Unlike capacitive screens which react to the human finger, resistive technology is based on pressure. Combined with the somewhat small size of the screen (it feels smaller than 3.5” to me, possibly due to being somewhat recessed into the panel), and it makes navigation difficult at times. Picking a main function is easy enough but choosing the name of an artist from a list required fingernail action. Eventually I started using a stylus from my old Samsung Epix smartphone - I did much better with the stylus. Resistive screens were not always bad, but in this case I do feel that it is a compromise.
 
I don’t know the resolution of the screen but I’m guessing it is not very high – I’m guessing it is 320x240. It does not look as clear as my similarly sized LG Optimus screen, nor the larger Squeezebox Touch. There appears to be some dithering as well, like it can’t reproduce the full spectrum of colors. It looks decent enough from arms length, and it isn’t bad enough to render it unusable… but it won’t win any beauty contests. I also notice what appears to be a dynamic adjustment of contrast: the screen gets slightly darker or lighter, ostensibly based on lighting conditions in the room. The problem is that this happens seemingly at random. It isn’t as bad as it sounds, and the difference between light and dark is not all that noticeable. But I don’t have a good explanation as to why it happens.
 
 
FEATURES
The 8600 has all the basic functionality one would expect from a streaming audio player. It uses the vTuner portal for internet radio, it features Aupeo! streaming, it can access content via a UPnP connection to a computer or NAS, and it can play local content through one of the two USB ports. It has built in Wi-Fi as well as an Ethernet port for a hard-wired connection. A 1/8^th inch headphone jack rounds out the connectivity options. It’s a pretty robust feature set overall, with all areas represented to some degree.
 
The 8600 handles a good assortment of formats: AAC, OGG, MP3, WMA, WAV, and FLAC. It will accept FLAC files up to 24/96 resolution, but they get converted down to 16/48 prior to playback. This applies to both analog and digital outputs. While full resolution playback would be ideal, I do appreciate the fact that I don’t have to tiptoe around my collection, as was the case with the NAD C 446. On the plus side, gapless playback is supported.
 
The 8600 is unique among the streamers in this roundup, in that the main unit does not have a display or any buttons – that is all handled by the remote unit. Users do have the option of using Teac’s myWAP app for iOS instead of the included remote. No specific app is available for Android, though any UPnP/DLNA control app will do the trick. I’ll show some pictures of the myWAP app in action – it’s a fairly straight forward program, adequate and useful but not amazing.
 
The controller is based around the touchscreen but it does have some physical buttons on top – a power button and dual buttons for volume up and down. Volume adjustment is handled in the digital domain, and affects the analog and headphone outputs but not Toslink.
 
This unit has another fairly unique feature in the ability to record internet radio stations. It won’t work with Aupeo! but any standard internet radio is fine. I didn’t use this function but I could see it coming in handy for fans of talk radio.
 
 
SETUP
Getting the 8600 to work in my system was fairly straight forward. Through the controller, I simply entered my passkey for the network, and I was all set. I do wish it used a QWERTY keyboard layout instead of alphabetical.
 
Insert a USB drive and the 8600 will automatically scan for files. It takes a while but only has to be done once. The 8600 worked perfectly with my 500GB portable hard drive without an external power connection.
 
One curious aspect was how to configure vTuner and Aupeo! with customized accounts. Both will work straight from the box in generic form; vTuner will allow you to browse by categories such as genre or location, and Aupeo! will give you 128k steaming quality. But I couldn’t figure out how to register either of them to get a more personal experience. The manual was no help either. Eventually I discovered that the myWAP application allowed me to enter a name and password for Aupeo!, which didn’t seem possible from the standard controller. I’m still working on getting registered with vTuner so I can build a list of favorite stations. This seems like it could have been implemented better.
 
USE
The 8600 is very easy to use. Upon startup you are presented with a main screen asking what function you’d like to play: USB, Internet Radio, or Audio Server. Choosing one of those will lead you to further options which apply to that function. This is best illustrated by pictures.
 
The “now playing” screen looks very similar no matter what source is being played. I like the fact that it always displays the bit rate and sample rate, though I do miss seeing the compression format. You get album title, track title, and artist information when playing your own music or Aupeo! stations. Internet radio isn’t as informative, though it varies from station to station.
 
The now playing screen does show album art, though I had some difficulty getting it to display consistently. I’m guessing there is some maximum resolution corresponding to the low-res of the display itself. This wouldn’t be a huge deal if the spot remained blank or had some reasonable logo indicating that no album art is available (like the way it is done on the Squeezebox Touch). The problem is that Teac uses a terrible stock photo whenever the album art won’t work – which is quite often. To make matters even worse – after a short period of inactivity, the player switches to a different screen, with larger album art and less details. This is great for a real album cover, but terrible for the stock photo. Scroll down to my pictures to see just how bad this looks. Thankfully most internet radio stations have their own art, as does Aupeo!.
 
The unit was reasonably quick during normal use – navigating through folders, skipping ahead to a new track, loading a new radio station, all was fairly smooth. Volume adjustments had a few seconds of lag, to the point where I wasn’t sure if my button push had registered. But this is one of the only units to have remote volume adjustment, so I shouldn’t complain.
 
The myWAP app was a nice upgrade over the stock remote – not so much for the features, but rather for the fact that it is being used on an iDevice with a better screen. I use an iPad for it and find it much easier to navigate through artists or stations. I’ve also used other programs such as the free iMediaControl, and they all recognized and controlled the 8600 without issue.
 

Main page
 
 

Selecting USB
 
 

Initial file scan
 
 

Navigating the drive
 
 

Tagging is key with large collections, as with any device
 
 

This is the stock photo they use when album art won't display....
 
 

I expected the lovely Marta Gomez and got this guy instead
 
 

This is what it looks like when album art works
 
 

Larger view of proper album art
 
 

Internet radio portal
 
 

The usual vTuner options 
 
 

Finding a station
 
 

Playing a station
 
 

Aupeo! station
 
 

Notice the "love/hate" buttons for rating this song
 
 
 
SOUND QUALITY
I mentioned before that the 8600 shares a similar appearance (internally) with a good quality soundcard. Continuing that trend, it also has a light green 1/8^th inch headphone jack, similar to many soundcards. I don’t know anything about the internal design but it’s a safe bet to assume we are dealing with opamps and perhaps an integrated headphone driver chip.
 
Keeping that in mind, the 8600 actually sounds pretty decent. It reminds me a lot of the Squeezebox Touch, which I also found surprisingly good through the headphone and analog outputs. There is plenty of room for improvement but it could also be much worse.
 
Starting with the headphone out: there isn’t a ton of power here. You can forget about driving an HE-6 or even an LCD-2 with any amount of authority. But you knew that already. For somewhat modest loads such as Grado, Audio Technica, Ultrasone, and most IEMs, the Teac sounds pretty darn good. It has a nice even tone, not too warm and not too cold, with a reasonable transparency that allows details to shine through. It isn’t the most refined amp in the world – Grados and Audio Technicas could sound a bit shouty or harsh (as they tend to do) on certain material, and busy passages sometimes came across as congested. It also didn’t sound great with 300 ohm Sennheisers, lacking the proper drive to control their low frequency response. Still, considering my expectations when I saw the green mini-jack, I’m fairly impressed. It actually sounded quite good with the majority of my custom IEMs, easily on the level of a good soundcard from Asus or Creative.
 
The analog outputs are of similar quality, but obviously don’t have the same issues with drive power. They are fairly clear and neutral, with a moderate amount of detail and a good overall balance. Once again I’m reminded of the Squeezebox Touch. Neither will blow you away in terms of absolute sound, but both may surprise you compared to what you would expect from such a small box. This device would fit right in with such gear as the Matrix M-Stage and AKG K701. The term “mid-fi” comes to mind, and I don’t mean that in a derogatory way at all. The sound is noticeably better than the Grace Tuner, roughly on par with the Squeezebox Touch, but not on the same level as the NAD C 446. If I had to choose between them, I think the Squeezebox is ever-so-slightly better than the Teac, but the differences are negligible.
 
The 8600 has an optical output, so it can be upgraded with an external DAC. When I tried some low priced options like the Hot Audio DAC Wow, I got just a modest improvement over the analog outputs. When I moved up to a nicer DAC such as the Yulong D100, I noticed a larger improvement. This means that the 8600 won’t automatically be the weakest link in a system until it gets built up to a higher level. Once there, a user could add a nice DAC and be all set.
 
I did notice that the 8600 sounding better in situations where the DAC has good jitter reduction capabilities. A good test of this is the Matrix Cube DAC with defeatable asynchronous sample rate conversion. The ASRC process helps reduce jitter significantly and it did sound much better when activated. Turning it off resulted in relatively blurred transients, a collapsed soundstage, and less overall realism. If I use a high end, low jitter CD transport like my Marantz SA-1, the ASRC switch is basically imperceptible. What that tells me is that the 8600 has somewhat high jitter on the digital output. Most decent DACs these days have at least some type of jitter reduction capabilities so this is less problematic than it would have been in the past. I’ve noticed similar results with lots of CD transports, even some from “big name” audio companies. Considering the price and target market of this unit, I don’t think it will likely be used in a high end system where this will be a major drawback. 
 
I was curious about the mandatory downconversion process when playing hi-res material. Listening to 24-bit/96kHz tracks and having them drop down to 16/48, then switching to the overall similar sounding Squeezebox Touch (which handles 24/96 tracks sans reduction), I did seem to perceive a small decrease in quality. But it was far from being drastic, and I may not have even noticed if I didn’t know what to listen for. I suspect that the resolving capabilities of the 8600 are just not high enough to make this a big issue. In any case, I’ll gladly take handicapped hi-res playback over none at all.  
 
CONCLUSION
The Teac WAP-8600 is an interesting device. It looks like a wireless router on the outside and a soundcard on the inside, which is basically how it performs (and I mean that in the best possible way). The sound is good enough to use in most real-world systems, and it offers a nice mix of features for the price. In many respects is a viable alternative to the Squeezebox Touch - for someone who prefers UPnP over Squeezeserver, or just wants a stealthy component that they can hide away rather than displaying on their shelf, the Teac might be a better fit.
 
My biggest issue is with the controller unit – it looks like a remnant of the last decade, with its low resolution and resistive touch panel. It is not totally unusable, and it does get the job done, but it isn’t pretty or fun to use. The myWAP application for iPhone/iPad is a good alternative, but not everyone wants to use their iDevice as a remote. Other software can be used for Android or iOS and that works quite well, but the point remains – these are all ways to get around the flawed stock controller. If your tendency is to select an album and play it through then it won’t be so bad. But if you are more the “hands on” type then it is likely to frustrate.
 
Why would a high-tech company like Teac use such an outdated design? Searching for an explanation, I did a little more research. The WAP-8600 is an upgrade of the older WAP-8500. That model used the same controller unit and was released in 2008 or possibly 2007. If you figure it took a little time for Teac to design and release it, then it seems likely that the controller unit was created 5-7 years ago - in a time where resistive touch panel devices were much more common. That helps explain it but doesn’t necessarily excuse the fact that it is still in use.
 
Aside from that, the WAP-8600 is a quality device. I would recommend it, with reservations, if the price was right. But since it sells for roughly double the price of the Squeezebox Touch, I’m not sure exactly who Teac is marketing this to.
 
Or maybe it is just at the end of its life cycle – Teac has a new streaming box, the MP-H01, due out shortly. It does away with the controller aspect, instead relying purely on Android or iOS devices as remote. It features Airplay and DLNA compatibility. It looks very attractive externally, and all signs point to it being far superior to the WAP-8600. I’ve seen various prices translating to roughly $300-350 which seems very reasonable to me. If someone is interested in a streaming device and likes the idea of buying Teac, I’d suggest waiting for the new MP-H01 to become available.
 
 
 

 
NAD C 446
 

 
BACKGROUND
NAD has been around for a long time – next year marks their 40^th anniversary in the audio biz. Many an audiophile got their first taste of “proper hi-fi” through the NAD 3020 amplifier, and there have been literally dozens of highly significant models released since then. Today you can buy a wide range quality gear from NAD, from the $379 C316BEE to the $6,000 M2. And that’s just the integrated category – they also do CD and DVD players, dedicated amplifiers, and other types of gear.
 
Link to the C 446 on the NAD website.
 
 
OTHER MODELS
This C 446 is a new release from NAD. The “C” stands for “Classic Series”, which means it matches aesthetically with the other C-series disc players and amps. NAD recently unveiled some higher end components from their Master Series - The M50 ($2500) is the playback device and the M52 ($2000) is the storage device. These are so new that they aren’t yet on the NAD website as a write this, and are obviously geared towards a different market than the C 446.
 
DESIGN
The C 446 is a full size component that will look right at home on an audio rack. It is roughly the size and shape of a good integrated amplifier. If you already have some NAD components in your system from the Classic Series, the C 446 will be a perfect match. Even if you don’t it should still blend very well with your equipment. I’ve always appreciated the balance NAD has achieved with the C series – they look somewhat upscale yet still understated.
 
The C 446 has a nice clean front panel that still allows control of most functions. Select your source, scroll through various stations or files, play or pause; it’s all there. The display is a VFD type similar to what you would find on a decent CD or DVD player, though is a bit taller to accommodate the extra lines of info needed here. Many devices in this category have large icon driven displays, and often show album art, but NAD sticks to a more classic styling.
 
Out back we find plenty of connectivity options: antenna connections for AM and FM radio, analog RCA outputs, Toslink digital output, LAN port, RS232 port, NAD iPod dock port, and finally connections for a 12V trigger and IR flasher. There is also a spot to attach the included WiFi antenna. Many of these connections are things that you typically find on higher end gear, in order to integrate into a custom installation. I personally didn’t use the 12v trigger, IR input, or RS232 port, but I appreciate the fact that NAD included them. Power is connected through a standard detachable IEC cable.
 
Internally, we find lots of spare room in the case, though not as much as we saw with the Grace model. NAD certainly could have made this into a more compact unit, but that would mean A) it would no longer take up a full spot in a standard audio rack/shelf, and B) it wouldn’t match up with any of the other Classic Series components. So I think they made the right choice. If this were a CD player, much of the empty space would be occupied by transport components, which the C 446 obviously doesn’t need. So I don’t think it is totally fair to complain about the space inside the case.
 
There are basically three main parts to the design: power supply, main board, and radio tuner. The radio tuner is an enclosed part so I can’t see inside. It sends the signal to the main board where a TI PCM1808 ADC converts the analog data into digital.
 
The power supply uses a somewhat small transformer as part of a more complex design, flanked by over a dozen capacitors of various sizes. NAD has long been known for their quality power supplies, and although this model doesn’t appear to be as robust as the supplies used in their power amps, it doesn’t really need to be either.
 
The main board of the device is where we find the various bits that make the C 446 tick. The heart of the design (as far as audio reproduction is concerned) is a Cirrus Logic CS4392 DAC and twin NE5532 opamps. Neither of these are considered cutting edge at this point, yet both have been used in numerous high end designs. The CS4392 was once popular in audiophile disc players from such companies as Luxman, Myryad, and Unison. And the venerable NE5532 shows up everywhere -  from expensive CD players like the Exposure 2010S to the new Cambridge 751BD universal player, as well as the Music Fidelity M1 DAC (a Stereophile component-of-the-year runner up). I don’t mean to imply that the C 446 is on the same level as those units simply because it uses the same DAC or opamps. My point is that these inexpensive components can and are used in a variety of applications, from low end to high.
 

 

 

 

 

This is the "empty space" I mentioned - If this was a CD player, there would be a big square transport section taking up most of the leftover area
 
 

Cirrus Logic CD4392 Delta-Sigma DAC
 
 
 

AM/FM tuner
 
 
 

Power supply
 
 
 

Power supply top view
 
 
 
 
BUILD QUALITY
The C 446 seems rather well built and certainly meets my expectations for an $800 component. It isn’t fancy, but tolerances are tight and finishes are well done. The gold “feet” on bottom are a nice touch, adding a bit of class to an otherwise low-key design. Despite the case appearing somewhat empty, the device weighs in at over 10 pounds, which is fairly substantial.
 
I really enjoyed the included remote control. It felt good in my hands and seemed to be laid out well. The only complaint I had: I didn’t end up using the number keys or transport keys much, so I was a bit disappointed that they took up so much real estate. Aside from that it was about as good as it possibly could have been.
 

 
 
 

 
 
 

 
 
 
FEATURES
The C 446 aims to be the heart of your system, and has enough features to support that goal. It can play AM/FM terrestrial radio. It can access thousands of internet radio stations using the vTuner content portal. It can stream audio tracks from a computer or NAS using the UPnP protocol. It can play tracks directly from a USB stick or portable hard drive through the front panel USB input. It can also access Last.fm, which requires a paid account at $3/month. Euro versions support DAB and DAB+ radio. That is a lot of options for getting content.
 
Breaking those features down into more detail:
 
AM/FM – A unique feature here is that the stream can be passed out in digital form through the Toslink output. This could make system setup easier, though for most folks it won’t matter.
 
Internet radio – vTuner works quite well for organizing your favorite stations. It is much easier to do all that legwork on your computer and then access it through the C 446, rather than do it all from the device itself. I have a “favorites” menu setup, and inside I keep things organized into different genres: classical, jazz, rock, pop, world, Christmas, electronic, reggae, etc. It is easy to search for stations and add them to the proper section. Since vTuner allows filtering by bitrate (they label it “fastest speed”) I was able to quickly find high quality 320k mp3 stations for most genres, which sound pretty darn good.
 
UPnP playback – The C 446 can play FLAC, MP3, WAV, AAC, and WMA files, up to 24-bit/48kHz. That limitation means it doesn’t handle what we usually consider “Hi-Resolution” tracks, though one could argue that tracks such as the Bowers & Wilkins Society of Sound releases at 24/48 qualify as Hi-Res. They certainly sound good enough. Still, this limitation means that some care is required when organizing or selecting files for playback. When I accidentally select the 24/96 version of “Paper Airplane” by Alison Krauss & Union Station, the C 446 gets stuck on “Buffering” and never finishes.
 
USB playback – I tried a few flash memory drives, as well as a 500GB Seagate portable hard drive, and had (mostly) good luck with all of them. I did run into an issue though: when I power down the C 446 with a USB stick or hard drive plugged in, it sometimes fails to recognize the drive when I later power back on. A quick unplug-then-plug-back-in maneuver rectifies this situation. NAD likes to use the term “USB memory stick” when talking about the USB port, as if to discourage use of an actual spinning-platter hard drive. My first try was to add a dozen test albums to the Seagate drive, and it all worked out perfectly. That drive has since been paired with a different streaming player and loaded full of hi-resolution files. I later tried plugging it back in to the C 446 and it recognized the drive by saying “Attached”, but went no further. This is probably caused by some issue with the amount of files or possibly even the sizes of the files - some of the Reference Recordings HRx 24-bit/176.4kHz tracks are simply massive. But I don’t have the time or energy to erase the drive and try it again. Portable USB hard drive support is almost always a bit touchy in my experience, so I really can’t predict if your particular drive will work or not.
 
The manual gives some limitations to watch out for: FAT32 format, maximum of 65,408 total files in a maximum of 128 folders. As long as you work within those parameters most drives should theoretically work. Some drives may require an external power source (like a powered hub) but mine didn’t. Surprisingly I found that I didn’t use USB as much as I had anticipated. UPnP worked well enough so I usually stuck with that. Your needs may differ.
 
Last.fm – The literature on the NAD website says the C 446 features “ …support for cloud music services such as Last.fm”. That implies that Last.fm is only one example of several. But in reality it is the sole choice. It also requires a $3/month premium account in order to work with the NAD (Last.fm free accounts work with computers only). I hope that NAD has plans for adding more services in the near future. MOG or Spotify might be a challenge due to their more complex user interfaces, but Pandora and Aupeo! would be a perfect fit here. Both offer free services so C 446 users could get up and running without spending extra money initially. The remote already has buttons for Like/Dislike so it should be a perfect match.
 
Interestingly, NAD chose not to design a specific App for Android or iOS users to control the C 446. Instead, users can choose from any one of a large number of existing UPnP remote Apps. I’m personally using Skifka on my Android Tablet and iMediaControl on my iPad. Both are free and both do a reasonably good job of handling basic remote functions. Other options include Smartstor Fusion Stream for iOS (free) and PlugPlayer for Android or iOS (not free). I do wish that NAD had offered some suggestions for what programs they like. I suspect the target market for C 446 includes folks who aren’t extremely computer savvy, and some tips on which options to try might have been appreciated.
 
 
SETUP
The C 446 was quick and easy. After plugging it in and telling it to use my network, I was prompted for a password, and was up and running from there. I used www.vTuner.NADelectronics.com to start a vTuner account and register my unit. Since I already had UPnP running well with my Windows 7 based PC, I was all ready to go.
 
 
 
USE
The C 446 was easy to get the hang of. Using the left and right Source buttons on the remote or the front panel, one can quickly cycle through the various functions. The screen was well laid out and generally bright enough, though sometimes difficult to read from across the room. This is not due to any deficiency in clarity or brightness but simply the font size. I see no way to avoid this while still presenting a similar level of information, and as it stands it is certainly no worse than most disc-based players.
 
The top line of the display always tells what source you are listening to. The next level down gives you specific information about the song: each push of the “info” button switches this line to show something else – song title, artist, album, then compression type and bitrate. There are variations based on what source you are using but it is generally similar. The bottom level shows status such as “playing” or “paused”, along with elapsed time. I tried to capture the display in action as that will probably give you a better idea than my attempted explanation.
 
Moving through files or radio stations is fairly easy. The remote control has a nice 4-way rocker plus an “enter” button in the middle, and that’s what gets used 90% of the time. You can list music by the usual criteria such as artist, genre, album, etc. As with any device of this nature, the results depend on how well your library is tagged. My one complaint here was that scrolling through a long list could take a while. There is a search option but it is inconveniently located at the end of the file list – by the time you scrolled down to it, you would have already passed whatever you were looking for. It would make way more sense to place it on top instead.
 
This issue was solved through the use of an iOS or Android device as a remote. Scrolling through your list on a big touchscreen device is by far the easiest way to deal with a large music library. The addition of album art is a small benefit as well, but it is mainly the navigation that I’m concerned about. If you have a smaller library (or just more patience than I do) the standard remote is perfectly fine, but for huge collections a smartphone really upgrades the experience.
 
In terms of speed, the C 446 was pretty impressive. Boot up takes a little longer than I’d like, but once it was up and running things moved along quite well. Selecting my large library from a networked computer caused just a short delay, and it would probably be shorter if I had a faster network. Playing songs from USB was near instantaneous, and UPnP playback was quick too. Internet radio stations took a second or two to load, occasionally longer when they are very far away. I never ran into any buffering issues, and had no interruptions once playback had begun. I did occasionally get errors when selecting internet radio stations: A message saying “Media Invalid” would display and the unit would just sit. I found that the solution was to simply back out to the prior menu, then reselect the same station, and it would always work fine the second time around. A minor annoyance at worst.
 
Last.fm is not my favorite choice as far as music services go, and as I’ve mentioned it is the only music service available on the C 446 at the moment. For one thing, the bitrate tops out at 128k. That’s not any better than the average internet radio station, and actually worse in many cases. I’ve used it before but don’t currently have a premium account. I tried a free account just to confirm that it won’t work with the C 446. Consider it confirmed. I’m hopeful that at least Pandora will be added as an option, but I have no specific information about whether or not that is in the works.
 
Some screenshots of the unit in action. These were difficult to capture due to lighting. Where there is any blur or apparent artifacting, it is because the display was changing at that moment. 
 

Boot screen
 
 

Opening menu
 
 

Favorites folder
 
 

This is how the screen first displays when a station is selected
 
 

Hitting the "Info" button shows the genre
 
 

Push it again for a description
 
 

Push it again for bitrate and compression format
 
 

Push it again for song information
 
 

Using a USB drive filled with music
 
 

Starting at the top of the list of artists
 
 

Then scroll all the way down to the bottom
 
 

Eventually there is a seach function - which would be more easily accessed if it was on top of the menu
 
 

Last.FM requires a premium account - I tried a free one and got this result
 
 

Leaving a USB drive inserted would sometimes give me this error
 
 

Remove the drive, plug it back in, and things are fixed
 
 

Internet radio sounds pretty respectable at 192k 
 
 

This error popped up once in a while but was an easy fix
 
 

Here I try to load a 24/96 track from the Head-Fi/Chesky album "Open Your Ears" 
 
 

But all I get is this screen
 
 

Standard 16/44.1 or 16/48 FLAC playback works great though
 
 
SOUND QUALITY
The NAD C 446 has been a roller coaster ride for me in terms of sound quality. When I first plugged it in and used the RCA outputs with my speaker setup, I was blown away by the superb analog-like sound I heard. It had warmth, drive, and a wonderfully smooth top end that seemed perfectly suited for a device like this. Even though I was primarily listening to lossless files at the time, I knew that at least some of my future use would involve lesser quality material – I figured this was the perfect voicing to give the unit.
 
Things changed a bit when I started comparing the C 446 analog outputs with some of my nicer DACs. In direct A/B comparisons, I noticed that the top end on the NAD wasn’t just smooth – it was actually missing some details altogether. The unit still sounded warm and inviting but the glossed over detail was a deal breaker for a while.
 
Eventually I think I got acclimated enough to the sound signature, and swung almost all the way back to my original position. This was just a good sounding unit with its own character, and unless I compared it to a $1k+ stand alone DAC it held up pretty well. It wasn't a detail monster but did an admirable job of balancing strengths and weaknesses
 
Bass reproduction was clearly one of the strong points of this design. From punishing dubstep to slap bass funk to the amazing Gary Karr on double bass, the C 446 handled it all in a very fun yet convincing manner. It can’t quite match the depth or dynamics of the best DACs and players I’ve heard, but the NAD unit is still very pleasing on its own.
 
Mids sounded well defined, if a little on the rich and warm side of neutral. Once again this seems like an optimal choice given the variety of material that will likely be played. Instruments and voices sounded realistic enough and I felt that the balance of technicality and emotion was just right. During really complex passages I noticed that there was a very slight blurring taking place, making it more challenging to focus on individual instrument placement (compared to my reference units). But on the whole this is a minor complaint.
 
Highs were a bit of a stumbling block for me. As I mentioned prior, it took me a while to figure out what to make of the C 446 sound signature, and the highs were chiefly to blame. My conclusion is that with the right expectations, the C 446 has a pleasantly forgiving tone, which will satisfy many but certainly not all potential customers. Everything is still there – cymbals, triangles, and various other percussion instruments are clearly rendered if not quite perfectly lifelike. If you are the type who demands crisp, hyper-detailed sound with sparkling highs, the C 446 (when used by itself) is probably not the best source for you. If you are willing to live with a smooth, flattering sound where poor recordings benefit, occasionally at the expense of hindering excellent recordings, the C 446 sounds pretty good overall.
 
Pairing the C 446 with an external DAC worked out nicely. The sole digital output is a Toslink optical connection – I would have liked to see a coaxial digital connection as well, but it isn’t that big of a deal. The main benefit I see with coaxial is the ability to work with 192kHz sample rates, where optical generally tops out at 96kHz (in practice if not in theory). Since the C 446 is capped at 48kHz this limitation doesn’t come into play. Still, if only for the sake of convenience, a coaxial output would have been nice. In terms of sound quality I didn’t find the C 446 to be a significant factor – which means it makes for a high quality transport.
 
COMPARISON
To help gauge how the unit would stack up against similarly priced competition of the disc-spinner variety, I compared it directly against a few other players. The C 446 seemed easily more capable than the somewhat entry level Denon DCM-390 and Marantz CD6002 players. The Marantz was superior to the Denon but neither could match the dynamics or resolution of the NAD. Stepping up to a Cambridge Audio Azur 650C ($750 when new), the C 446 was different but roughly equal. The Cambridge had a more detailed sound that also seemed more open and spacious. It was less congested during complex passages, and had more pinpoint imaging. In contrast, the NAD seemed smoother, warmer, more rhythmic, less clinical, and overall more inviting for long term listening. I could see either one being declared superior based on listener preference, but I personally think they are more or less on the same level. My choice would depend on what gear I would be pairing it with, and what music would be played.
 
I didn’t do direct comparisons with more expensive units, but I don’t think the C 446 would compete with some of the better ~$1k units such as the Rega Apollo. Obviously high quality speakers or headphones and proper amplification would be required to discern the differences.
 
CONCLUSION
The NAD C 446 is a really enjoyable unit. Expectations run somewhat high at $799 and in my mind the unit really delivers, doing an outstanding job of balancing its wide array of features. It looks suitably high end and is sonically competitive with traditional disc players in this price category. As NADs maiden voyage into the realm of streaming audio I’d say they have done well for themselves.
 
The trick here is going in with the proper expectations: knowing what the C 446 can and can’t do is really key to determining if it will be a good fit for your system. Those seeking a fancy color display complete with album art should obviously look elsewhere.  Folks who judge gear by the complexity and prestige of their individual parts will not find enough bragging rights here. But go in with an open mind and a willingness to judge based on results rather than chip specs, and you are likely to be impressed.
 
Clearly the 24-bit/48kHz limit will turn off some users. And I do think the issue is a valid criticism. But as I listen to Cara Dillon, or Samuel Yirga, or Radiohead, or Ola Onabule, or Tom Petty, or The Unthanks, or others in 24-bit/48kHz FLAC from B&W, Pristine Classical, and other sources, I can’t help but think that I AM in fact hearing what I consider Hi-Res audio. But I agree that it would be convenient to play the rest of my collection and not have to worry about sample rate issues. Especially since many of my other streaming audio players do allow that. At the very least I think NAD should add an error message so users know when they have selected an improper file with too  high of a sample rate. The current "buffering" message gives a false hope that the track is going to play, which is not the case.
 
Further criticism? The lack of Pandora or other streaming services, the single digital output, the failure to provide recommendations for remote control software. None of these are deal breakers in my eyes, and two of them are easy enough to fix if NAD wants to – making the C 446 go from “really good” to “exceptional” with a single firmware update.
 
I see the ideal customer for the C 446 as someone who already has a fairly nice system. They are heavily invested in their current components but want to add a new level of versatility. The C 446 analog output would be fed into their high quality pre-amp, and the unit would fit on their audio stand just like the other components. This customer has no interest in a touch screen interface. They may eventually use iOS or Android for control but will get by just fine initially with the standard remote. The C 446 is a good combination of functionality and simplicity, so even the most hardened Luddite should be able to figure it out.
 
Like every streaming audio player I’ve experienced so far, the NAD C 446 is not perfect, and it won’t be ideal for everyone. But it you find yourself in its target market I highly recommend looking into it. Being from an established firm like NAD has benefits too – you are much more likely to find this model at your local dealer. Play with it, listen to it, maybe even arrange an in-home trial. You might be glad you did.
 
I’d like to extend a big “Thank You” to Peter Hoagland of Lenbrook, parent company of NAD and PSB Speakers, for loaning me this review sample. Your generosity to the HeadFi community is much appreciated. I’ll be sending the unit back soon and I already miss it.
 

A very easy way to add functionality to a traditional audio system without using an actual computer. It can stream music from a computer, SD card, thumbdrive, or a NAS, access thousands of internet radio stations, link with free or premium accounts from Pandora or Aupeo!, and even do standard AM/FM radio. When used with an outboard DAC, it actually sounds very acceptable for such a low priced device. 
 
 
Link to my full review, embedded in my thread about streaming audio devices:
 
http://www.head-fi.org/t/582370/streaming-audio-devices-review-and-information-thread-work-in-progress#post_7922531
 
 

 

 

 
 
 
 
INTRO
 
I was chosen by V-MODA to be part of their “M-80 audio voyage” program. They chose 10 members from the forum and gave each one a free set of their new Crossfade M-80 on ear headphones, complete with custom engraved side panels. With an MSRP of $230 for the headphones plus $20 for the custom engraving, that’s theoretically $2,500 being given away to forum members – quite a generous showing from V-MODA. In return for this, we were asked to participate in a private sub-forum, discussing our impressions, giving feedback, and ultimately posting our reviews for the rest of the community to see. We were assigned an impartial 3rd party moderator and were never told anything as far as limitations to our opinions. If all 10 of us hated the product, V-MODA would have given away $2,500 worth of gear in exchange for 10 negative reviews.
 
Some of the other reviews are already posted, so I won’t duplicate their efforts as far as documenting every feature, nook, and cranny of the M-80. I’m going to make this relatively short and to the point. My contribution is going to focus mostly on the subjective aspects of fit and sound. I’ve probably got more experience with higher end headphones than most of my fellow audio voyage members, so I’m coming at things from a different angle than many of them. In contrast, many of them seem to have more experience with this class and type of headphone, so by no means am I saying I’m the most experienced or qualified participant of the group. We all have our various strengths and knowledge base, and that should make for a variety of perspectives.
 
I do have to mention one thing though – historically, I’ve never done well with supraaural headphones. The ultra lightweight style such as Koss Sportapro is comfy enough, but anything with some actual mass to it has left me uncomfortable after about 10 minutes of use. I don’t like using Grados with the comfies or the bowl pads. The last “portable” on-ear style headphone I tried was the Audio Technica ESW9. I thought I heard some potential for good sound in there somewhere, but the comfort (or lack of it) was such an issue that I gave up on them rather quickly. I suspect this had more to do with me than the ESW9 as I know a few people who find them very comfortable.
 
DESIGN
 
The M-80 is a compact on-ear design. When I first saw it in photos, I thought is would be much bigger than it really is. But it does seem to be in line with other portables such as the Beyerdynamic DT1350 and T50p. Check out pictures to get an idea of the styling – it really is a striking pair of headphones.
 
For custom engraving, I chose a skull design, which I think turned out very well. Unfortunately I forgot all about that company out there who makes (mostly) cheap headphones and puts skull logos on them… so in a way I regret my choice. But it still looks good so I shouldn’t complain. The design allows for easily swapping out the panels, so I could always switch to a solid black or solid red look if I wanted to.
 
The M-80 seems to fit my head better than any similar headphone I’ve ever tried. I have a big head, and correspondingly large ears, but the oval shaped pads of the M-80 do a good job of maintaining a seal. I find them more comfortable now, after a few weeks of use, than I did at the beginning. I think the pads have actually somewhat formed to the shape of my ear, but I’m also probably building up a tolerance for the pressure. I assumed they would have a vice grip when brand new, but it wasn’t so bad actually. Over time I do feel that they have loosened up by a small amount, but it didn’t require any deliberate bending. Doing so would probably speed things up though so it is an option.
 
Noise isolation: For my head and ears, the M-80 does not block a ton of sound. It is better than my open headphones like Grados, but inferior to my Ultrasone Edition 8 (which is small but still covers my ears more fully). And there is no comparison to any of my custom IEMs as far as isolation, but maybe that goes without saying. Examples – I can hear the refrigerator running if I sit within 10 feet of it. I can clearly hear cars driving by if I am outdoors. I can hear people talking to me at normal levels in the same room, and generally make out what they are saying. This is when no music playing. Once I play audio then background noise is less intrusive, but it obviously depends on the type of music and the volume it is played at. In their defense, the M-80s did not seem to leak any sound. I never got complaints from family members when I listened loudly in the same room as them. And this somewhat low level of sound isolation is not any worse than the Denon D7000 or Audio Technica W series models, despite those covering your ears completely.
 
BUILD
 
I find the M-80s to have a very robust build quality. These are one of the few headphones that I’ve dealt with where I believe I could drop them, sit on them, throw them in a backpack and forget about them as I travelled around… and they would make it through in good shape. V-MODA provides an excellent case, so you should be able to avoid this level of abuse, but it’s nice to know that they should last a long time. V-MODA gives a very generous warranty as well: 60-day “Test Drive” return policy, 2 year warranty, and 50% off replacement for life after the 2 years is up. They can probably afford to do all that because realistically there should be very few situations where an M-80 could actually be damaged.
 
PACKAGE
 
The M-80 has one of the most comprehensive packages I’ve seen in a while. Inside the (rather cool looking) box, you get the headphones themselves, a VERY nice “exoskeleton” hard case, a carabineer clip for attaching the case to things, and several cable options. People in the audio voyage program received 3 different cables: a longer regular cable for home use, a shorter cable with a mic and a single button, and then another short cable with a mic and 3 buttons. Their website only lists the M-80 as coming with the two shorter cables so I’m not sure how that works. Personally I got the most use out of the longer cable since I mostly listened on my big setup at home. It appears to be a standard 1/8^th inch connection, so custom cables could be easily swapped in if desired. I liked the Kevlar material of the cables, and they felt worlds better than the black rubbery stuff used by many others.
 
EQUIPMENT
 
This is the associated equipment I used for evaluating the M-80:
 
Source: JF Digital HDM-03S, Squeezebox Touch, NAD C446 (all media server/player type devices)
 
DAC: Violectric V800, Anedio D1, Audio GD Reference 7, Yulong D100
 
AMP: Violectric V200, Analog Design Labs Svetlana 2, Matrix M-Stage, Yulong A100
 
Cables: no nonsense options from Signal Cable, including Analog One and Analog Two interconnects, Digital Link coaxial, and Optical Link toslink connectors
 
Portable: Just so I wouldn’t be a snob, I tried some more humble portable players – Sansa Clip+, Sansa Fuze, iPod 5g
 
Music: I played a wide variety of stuff, ranging from MP3 rips of low quality punk albums all the way up to 24 bit/176.4 kHz HRx files from Reference Recordings.
 
I let the M-80 burn in for over 100 hours prior to using them, just in case.
 
LISTENING
 
My first impression of the M-80 was that is sounded surprisingly “big” for such a small headphone. Bass was big. Soundstage was big. Overall presentation was big, meaning that it had more of a forceful impact to it versus the delicacy displayed by some of my other headphones. But this was not unwelcome. I never expected a $230 headphone to be perfect.
 
The sound signature was certainly on the warm side, with bass being in the large to very large range. I was fairly impressed with the bass impact. While not quite on the same level as my other heavy hitters – the Lawton Audio LA7000 and the Unique Melody Merlin, it was still very satisfying. Kick drums had a convincing heft to them without being overbearing. Double bass, contrabassoon, tuba, and pipe organ all had deep extension and fairly good control. Once in a while I got the impression that there was a slight bleed-over into the midrange area, but this was infrequent, and when it did happen it was fairly minor. But again, overall bass performance was quite good. The fact that it is plentiful seemed to fit perfectly with my expectations or desires for this type of headphone. I don’t think I would want a completely neutral reference type sound from a headphone of this variety, and the M-80 seems just about right to me.
 
Mids seemed somewhat on the forward side but not overly so. I felt a good solid connection to vocals of both the male and female variety. I was halfway expecting (dreading?) a major V-shaped sound signature… there is a big V right at the beginning of the company name after all. But thankfully that was not what I experienced. These slightly forward mids are greatly preferable to the recessed mids I had feared. Because they have a lot of body, the mids keep pace quite well with the aggressive bass, and it tied in with the smooth highs which I’ll discuss shortly. I did notice that the mids fell short of ultimate resolution as compared to some of my higher end headphones. Subtle nuances were at times glossed over in favor of a more straight forward presentation. Considering the price and the form factor, I think this was a good choice to make. People are much more likely to be listening to these straight from an iDevice, portable DAP, or at best a portable amp, compared to some of the reference quality equipment I listened with. That’s not to say they sounded bad on higher end gear; I think my favorite combo was the M-80 with the ADLabs Svetlana 2 tube amp. It seemed to bring out as much micro-detail as could possibly be obtained and did great things for the highs.
 
As I mentioned, when describing the highs on the M-80s, the key word is smooth. If you are used to a sparkly presentation like the K701 or even Beyer DT880/DT990, these might initially seem a tad dull, but you would probably get used to it soon enough. Personally I felt that they struck a nice balance between being smooth and having good extension. In our private sub-forum, V-MODA founder Val Kolton discussed his disdain for false detail created by excessively bright treble, so obviously that same attitude shows through here. In most respects I agree with him, and once again I think the right choice was made here considering the type of headphone we are dealing with. I would not call this a “dark” headphone at all but some people may wish for slightly more zing to it on the top end. Proper amp matching can help to a certain extent, as can equalization, but this is never going to have the tipped up highs that some people might be looking for. I have no experience with the Beyer DT1350 but from what I’ve read that might be a better way to go for people chasing that sort of experience. As for me, I think the only downside I would occasionally complain about is the slight lack of that “airy” feeling as compared to some other headphones. I suspect that the M-80 has a significant drop off in the higher range, perhaps above 9-10 kHz or so. There is very little actual musical information up there in terms of fundamentals – in most cases (vocals for example) it is simply “air” in that range. Violins, flutes, piccolos, and cymbals all have overtones that extend well above 10 kHz, and all of those can still sound pretty darn good through the M-80s. Personally I don’t do a lot of critical listening of jazz or classical while on the go anyway, so it really isn’t an issue for me.
 
I want to talk a bit about soundstage. This headphone seems like it would be particularly variable when it comes to soundstage reproduction and imaging. This is not due to V-MODA doing a bad job with QA; Val Kolton has talked repeatedly about his efforts to minimize variability between samples. The real issue is with this type of headphone in general. Circumaural headphones are usually sized in such a way that they have just enough clearance to go around your ears, with maybe a little bit of extra wiggle room. Most users should be experiencing a fairly similar relationship between driver and ear. In contrast, the supraaural “on-ear” style can be placed any which way, usually determined by what is most comfortable to you. With all that room for placement, users could be getting very different impressions of soundstage size and accuracy. That being said, my experience with the M-80 was surprisingly positive. I didn’t think a sealed headphone with such a small cup would be conducive to a big soundstage, but that’s certainly what I got. We aren’t talking about a massive HD800 or K701 stage, but still quite respectable and “open” sounding. Maybe the “V-PORT” technology has something to do with this. Imaging is quite accurate, and would be respectable even for a full sized open headphone. So while the lack of treble bite might not be ideal for classical music, the open and spacious presentation helps make up for it.
 
I do not think the M-80 demands a potent amplifier to sound its best. All of the amps I tried had more than enough drive to push it to extreme levels, and even my portable devices never seemed underpowered. As always, quality is a factor, and my better sources and amps did bring out the strengths of the headphones more then my lesser models. But ultimately this is not a headphone that is ideal for discerning minute differences between gear. And it isn’t really meant to be either.
 
CONCLUSION
 
I must say that I’m pleasantly surprised by the V-MODA Crossfade M-80 headphones. My expectations were admittedly somewhat low, but they won me over in pretty much every aspect. Packaging and accessories are brilliant. Build quality is top notch and very fitting for a portable model. Comfort, a subjective thing to be sure, is better (for me) than any similar type of headphone I’ve ever tried. These things alone add up to a great user experience, even if that was all the M-80s had going for them.
 
And then there’s the sound. Large, solid, impactful bass that mostly stays well controlled. Warm, full mids that make any genre seem engaging. And a smooth balanced top end that is reasonably detailed but extremely forgiving of poor material or equipment. I enjoy these. A lot. Even at home when I have plenty of “better” options, these are still fun to listen to. That seems like a successful product to me.
 
Could they be improved? Of course! Every headphone has room for some tweaking, no matter how good. I could list all sorts of things that I might change – but in the end most of my issues basically stem from the limitations of the supraaural style of headphone. And this “dream headphone” of mine certainly would not be sold for $230. But for what it is, and what it accomplishes at that price, I tip my proverbial hat to the V-MODA Crossfade M-80.
 
So, Val…. How about that M-100?
 
 
 
 
 
 

See complete review here:
 
http://www.head-fi.org/t/575868/review-octet-matrix-de7-monitor-speakers-a-headfi-exclusive-review
 
For many people, these will be all the speakers you will ever need. They are clear, transparent, balanced, fast, and not picky about placement or amping. A seriously good value even at twice the price - I can't recommend them highly enough.

My full review:
 
http://www.head-fi.org/t/574418/review-violectric-v800-dac#post_7799058
 
In summary, this is one of the best DACs I've ever experienced, which is surprising since it only costs $1300. That's a lot of money, but actually pretty low for a top class DAC, which is what I consider this to be. In my personal experience I rank it below the Resonessense Invicta ($4k), MBL 1511E ($8k), and very very slightly below the now discontinued Anedio D1 ($1230), but above the Audio GD Reference 7 ($1900), Esoteric D70 ($6500), Wavelength Cosine ($3500), and of course all the usual suspects from Lavry, Benchmark, Grace Design, Musical Fidelity, Cambridge Audio, etc.
 
This DAC at $1300, paired with the matching Violectric V200 ($1k), makes for an ultra high end reference system that compares to almost anything out there.  

See my complete REVIEW HERE
 
In summary, this is an awesome sounding compact all in one unit. It will take the digital output from any basic CD, DVD, or Blu-Ray player and transform it into excellent audio without a lot of fuss. It has good jitter control, a transparent USB input, and enough power for most speakers in most rooms. The headphone amp is decent with low impedance headphones but excellent with higher impedance models. An excellent choice for someone needing a compact all in one unit.

See full review here:
 
http://www.head-fi.org/t/568054/review-audinst-amp-hp-portable-headphone-amplifier#post_7697280
 
In summary, this is a great sub-$200 portable amp. It's like Audinst took the already nice sounding amp section of their HUD-mx1 device, improved it by maybe 15 or 20 percent, and then made it portable. What's not to like about that?

This high end hybrid custom delivers on its promise of outstanding bass performance with very natural and well balanced mids and highs. Soundstage is phenominal and the entire presentation is somewhat unique. They could have gotten away with charging $1k or so like many other flagship customs - so although $779 is certainly not cheap, it is a relative bargain.
 
 
Link to my full review:
 
http://www.head-fi.org/forum/thread/566965/review-unique-melody-merlin-hybrid-dynamic-balanced-armature-custom-iem

http://www.head-fi.org/forum/thread/562428/review-kozee-infinity-x1-custom-molded-iem
 
See above for my in depth review. This really is a good product. The issue is with the company itself. As I mention in the review, they are not returning emails from customers. And when people do manage to track them down on the phone - they make promises that are apparently not kept. I like Kozee as a company - the product seems good and the prices are low. They just need to get their act together with regards to customer service. If and when they do, I'll be the first person to recommend them.