Previously known as sub30
Pros: Exceptional build quality – really solid and weighty
The iFi design language is attractively unique
Wireless capability with support for virtually every Bluetooth codec
Can serve as a BT receiver for your DAC/Amp stack
Stable Bluetooth connection with remarkable range
Comes with 2 antennae and an RCA cable
Components come from well-renowned manufacturers
Cons: That iFi at the center looks like a low-res pic due to the frosted cover (I don’t know, might just be me)
There’s no on/off switch
No USB input (understandable, but still)
4.4mm balanced output (an included cable in the box would have been much appreciated)

I would like to thank Karina from iFi Audio for assisting me in acquiring a loan unit of the Zen Blue V2. I would also like to express my gratitude to Sir Rico of Egghead Audiohub Philippines (local distributor in the PH) with providing the unit. I am sincerely grateful for this opportunity.

I am not an expert in this hobby nor claim to be an audiophile. I just love listening to music and am fond of writing articles.


The iFi audio Zen Blue V2 is an update of the model with the same name (released 2020). Its purpose is to convert your Hi-Fi setup into one with wireless connectivity. It has both digital and analogue outputs, with only BT input. It can also output via a balanced cable if ever you have amplifiers that support as such. The iFi Zen Blue V2 is available for purchase at the price of 190 USD. TL;DR – it’s as advertised and everything works properly, but I have a few complaints.

These were connected to my phone (Realme GT Master) and laptop via Bluetooth (varying codec), to the Topping L50 through RCA with the transducers used for testing.

Specifications and Measurements (from iFi audio):
ChipsetsQualcomm QCC 5100 Series (Bluetooth)
ESS Sabre (DAC)
InputBluetooth 5.1™ with AAC, SBC, aptX,
aptX HD, aptX Adaptive, aptX LL, LDAC,
HWA Codec
Output4.4mm Balanced
3.5mm S-Balanced (SE)
Frequency Response10-48K (-2DB) under LDAC
Output Voltage @ OdBFS2.05V (+/-0.05V)
Dynamic Range109dB (A)
Signal/Noise ratio111dBA/106.5dBA (BAL/S-BAL)
THD & N @ OdBFS<0.009% (BAL 6.5mW/2.0V @ 600Ω)
<0.03% (SE 100mW/1.27V @ 16Ω)
Output Impedance<50Ω
Power Consumption<2.5W
Dimensions158 (I) x 100 (w) x 35 (h) mm
Weight476g (1.05 Ibs)


Package: Unit itself. 2x antennae. Power adapter. User manual. RCA cable. General accessory instruction card.

Design and build:

The Zen Blue V2 follows iFi audio’s iconic design language. It’s a full metal build with the faceplate done in a brushed finish while the dark grey main casing is matte-like, effectively avoiding any fingerprint mark. Being an aluminum case, it has weight which one usually associates with quality and the word “premium.”

At dead center is a circular cutout with a frosted cover. Behind that is the word “iFi” that changes color to represent what codec is currently in use and doubles as an indication that the device is active. At initial pairing, “iFi” will light up with said specific color (please refer to the product page of the Blue V2 under “Tech Lockdown). The smaller circular cutout at the right, meanwhile, is there to show the sample rate. Moving on to that “iFi,”, it is rather undesirable. I have a feeling this was due to the use of that frosted cover, which in turn made the lines of each letter really soft, blurry and unclear, making it look like a poorly printed legend. It looks like a low-res pic.

The only negative I found on the build quality of the Zen Blue V2 is the BT pairing button that also functions to turn off the two LEDs of the device. Design-wise, it fits the whole image of the Blue V2 – color, shape and all of that. But the button just feels so cheap to use – out-of-place, in a sense. It’s very wiggly and when pressed, feels extremely plasticky. I understand that this button would likely not be used all the time. Heck, I’ve only ever pressed it for less than ten times. However, this small detail would have made the Zen Blue V2 perfect, build and design-wise (subjective), excluding the two stuff I will be talking about next.

A subjective dislike I have with the Zen Blue V2 is the lack of an on/off switch as well as the color of the antenna. The former is just a personal need of mine while the latter I find to not fit the color palette of the unit (antenna’s white) *shrug*


Connectivity and Features:

Input is purely via Bluetooth. SBC, AAC, aptX, aptX HD, aptX Adaptive, aptX LL, LDAC, and LHDC – these are specifically what the Zen Blue V2 supports. The jump from SBC to aptX HD/Adaptive is significant while aptX HD/Adaptive to LDAC is less apparent though still noticeable if you go back and forth. If you don’t, I say either of the two will satisfy most ears. Choose based on your use case as well as compatibility.

There’s not a lot of features to talk about. It can function as a BT receiver for your setup via its digital output. There are also analogue outputs – the standard RCA and a 4.4mm balanced that puts out ~2x the amount of Vrms.

Oh, I forgot to mention – it has this neat feature wherein a voice prompt is heard as you pair your device with the Blue V2, also including what codec is currently in use.

Now, onto sound… wait, how do I go about this?
*reviewed as a BT DAC

While the BT chip that iFi opted to go with for the Blue V2 is considerably higher end, it serves one purpose only – receive BT signal and provide support for whatever codec your device uses. The one that converts the signal itself is an ESS Saber DAC. Now, what model exactly? I do not know. It isn’t disclosed and the pic of the “guts” of the Blue V2 has the model name blurred out. Why they did that I also have no idea. There are screws at the back that suggests the unit can be “opened up.” However, as this is a loan unit, I have to respect iFi audio as well as Egghead Audiohub Philippines and ultimately decided not to do so. I did read on the internet, however, that as per iFi audio themselves, it is a “specialized DAC chip from ESS Technology’s Saber family to convert the signal from digital to analogue.” It may be safe to assume that the DAC chip is a custom-made model to serve the needs of iFi for its use in the Blue V2.

Moving on, the Blue V2 was “stacked” with the Topping L50 via RCA. For those that are concerned with the numbers, third party measurements can easily be found online. Said data suggests that the DAC part of the Zen Blue V2 is decent at what it needs to do and is nothing exceptional. Now, how does this sound like with transducers I tested it with? If you’re curious, read the section marked as a spoiler. You see, there comes a point where with DACs, it is simply highly subjective, where the power of the mind comes into play. I do not trust myself in this situation unless I have equipment with me that can level match these DAC paired with the same amp and the same transducer with the help of another individual (there’s also the filter used which may actually be the biggest difference between these DACs as well as how much voltage it outputs). Even with that, whether I can “hear” a change and confirm that it is not merely imagination or confirmation bias cannot be determined at the current time of writing this review. I simply cannot state with certainty and confidence how a change in DAC can produce audible change/s on the bass, midrange, treble and technicalities of the transducer.

The next sentences will be highly subjective (inconsistent, even, with my previous statement) and I cannot assure that your experience will be similar to mine. This is just to give an idea for readers that may buy the Zen Blue V2 not just for its wireless capabilities but also for its “sound.” To determine the change, I went back and forth with the Zen Blue V2 and the HUD100 MK2 (bypass mode, high power). There is really only one difference worth mentioning – the latter, somehow in some way, produced a more highlighted treble region. The former made no such change with the “sound.” I tried my best to volume match the two setups by ear. The HUD100 MK2 had this unpleasant sharpness, that while isn’t apparent at low volume level, became distractingly and fatiguingly harsh as I increased volume. The Zen Blue V2, meanwhile, maintained a neutral response without highlighting any frequency region whatsoever, consistent to any volume level.

Now, is this just my imagination and my mind playing tricks given that I have always heard of iFi having that “smooth” signature while the HUD100 MK2 has been described to be neutral (or bright-neutral, depending on who you ask)? No idea. Take from that what you may.

I am also on the table that as long as the DAC maintains a clean signal without objectively undesirable distortion (read: audibly bad measurement), it is more than enough. Also, I lean more towards the better measurements = better DAC table, most especially if one’s capacity does not allow them to possess several DACs of different “flavor.” If you need some change or want to tweak a frequency, there’s always EQ for that *wink*.


Battery Drain:

Not applicable as the Zen Blue V2 has its own power supply. Battery drain of BT connection is also negligible in today’s gadgets. But, generally speaking, the higher quality the codec, the less battery efficient it is.



1. There’s no 4.4mm to 4.4mm balanced cable included in the box. As it is a rather uncommon I/O in desktop setups, it would have been greatly appreciated if iFi provided as such.​
2. Bluetooth is nice, but where’s the USB input? I do understand that the Blue was purposefully designed and built for wireless connectivity as its feature. However, this makes it a one-trick pony with a beautiful chassis for close to 200 USD. That’s considered expensive in several areas of the world. There IS the Zen One Signature that has said input but that one’s around 300 USD. And just recently, iFi has announced their new Air lineup, specifically the Air Blue. That one will be selling for ~100 USD, albeit without the balanced out, digital out and now a plastic case material. Specs, when compared to the Zen Blue V2 suggests similar DAC performance.​
3. Again, like what I’ve mentioned before, why is there no on/off switch or button?

The iFi audio Zen Blue V2 is a wonderful device – IF you desire that Bluetooth connection in your setup. It has an abundance of outputs that should cover everything (both digital and analogue), supports virtually every BT codec in the market, with a beautifully designed case (IMO) and decent DAC performance based on measurements available online. However, there are certain areas worth looking into before you decide to buy the Blue V2. And, there’s the Air Blue, so it would be better to wait for reviews for that product and see how the Blue V2 performs against its little brother.

Test Setup:
Phone/laptop -> Zen Blue V2 -> Topping L50 -> Hifiman Edition XS/Sundara, Sennheiser IE400 Pro, Moondrop SSP, KZ DQ6, Smabat M2s

****If you have other questions/concerns with the DAC mentioned, feel free to message me****​


Headphoneus Supremus
iFi Zen Blue Review
Pros: Does what it says on the Tin
Easy to Use
Cons: Bluetooth is a limited format
a bit thin and sharp sounding in DAC mode
Simple, but effective
Hi Guys,

Todays review will be a bit shorter than normal as the piece of gear we are talking about is actually quite simple. The iFi Audio ZenBlue. The ZenBlue is a member of iFi’s slowly expanding Zen Range, and has the same form factor as the rest of the line. It offers a up very simple functionality as a bluetooth receiver and DAC. There is no volume control, headphone amp, XBASS or 3D features. There is one button on the front to pair with a device, and one on the back to switch from a Digital to Digital function, or use the internal DAC and operate via RCA outputs. You can also use a 4.4mm balanced pentaconn output on the rear, either to connect to another member of the Zen series (which makes sense) or a 4.4mm to dual 3pin XLR into an amp. The problem with that is pentagon to dual 3pin XLR cables will cost almost as much or more than the ZenBlue itself, so perhaps not the economical way to do things.

The ZenBlue is very simple in how it works. You screw in a short antenna which comes in the box, and plug it into the 5v included DC power brick. You then decide if you want to use it as a DD convertor into whichever DAC you prefer, or as a DAC itself using its RCA outputs. You then press the pair button on the front of the unit, which makes it searchable, and then on the device of your choosing, you pair with the ZenBlue. Thats it. Totally easy, totally simple.


I initially tried the ZenBlue as a DD converter into my Rockna Wavelight DAC. This worked well, and there was no latency between selecting songs on my computer, and hearing them come out my headphones or speakers. The same can be said for when I tried it as a DAC directly into my Kinki EX-M1 integrated amp.

Bluetooth as a technology does limit you to less than lossless levels of transmission. As far as I understand, it currently cannot transfer losslessly regardless of the CODEC you use. I did a bit of research and it seems that 320kbps mp3’s or the equivalent in other file formats are the best it can manage. Now, I personally don’t believe the difference between a 320kpbs mp3 and lossless is that big. The difference can be hard to hear, but there is certainly a slight difference, especially with material you are familiar with. With all that being said, as lossless streaming is becoming more and more common, and more and more affordable, I can’t recommend the ZenBlue for someone who is going for ultimate sound quality. Perhaps iFi’s newly announced ZenStream would be a better choice for those people. However, if you need an affordable, small, transportable DAC package that does bluetooth, maybe for a secondary non reference system, or in the kitchen for listening to tunes while you cook, or something similar, the ZenBlue would be perfect.

iFi’s new ZenStream, worth consideration for those who need “more.”
As a DD convertor, I didn’t notice it having a tremendous amount of influence on the sound. It simply passed through what it was being given. As a DAC, it was a bit thinner and sharper sounding than I am used to gear sounding from iFi, but again, for its price and use case, it is totally fine. Again, not for a reference system, but certainly ok for other uses. Not every piece of gear has to be top of the line, and its always neat to see a manufacturer coming up with other ideas and trying new things in the more affordable “entry level” market space.

ZenDac with ZenStream
Overall, the ZenBlue does what is says on the tin. It is an affordable, handy, and simple bluetooth receiver. Its not the best DAC I have ever heard, and bluetooth itself is a limiting factor, but within those boundaries, the ZenBlue actually works very well. If this is the sort of thing you have been looking for, and you feel it fits your use case, then I would recommend it highly. If it doesn’t, I would certainly check on the ZenDac, or again, the new ZenStream 🙂


100+ Head-Fier
iFi Zen Blue REVIEW
Pros: Balanced output
bluetooth connectivity
digital and analogue outputs
Cons: No option to turn off the front lights
About me:
Music lover and earphone enthusiast, most of my previous reviews are in spanish.

Disclaimer: iFi graciously lent me the Zen Blue in exchange of my opinion

Gear used:
Schiit Asgard 3, iFi Zen Can, Elemental Watson 2, Sennheiser HD560s, Fostex T50RP

About iFi:

iFi audio is a company with headquarters in the UK that since 2012 has launched more than 30 high quality audio products with one aim in mind "to improve your music enjoyment." You can find more in


Power:DC 5V
Input:Bluetooth 5.0TM with AAC, aptX, aptX HD, aptX Adaptive, aptX Low-Latency, LDAC, HWA/LHDC Codec
Output:Optical/Coaxial, Audio RCA L/R, 4.4 Balanced Line out
Frequency Response:20Hz – 20kHz <+0/-0.5dB (44.1kHz)
1Hz – 44khz <+0/-3.0dB (>= 88.2kHz)
Output Voltage @ 0dBFS:2.05V (+/-0.05V)
Dynamic Range:109dB (A)
Signal/Noise ratio:109dB (A) @ 0dBFS
THD & N @ 0dBFS:< 0.0015% 10k Load
Output Impedance:< 50Ω
Power Consumption:< 2.5W
Dimensions:160(w) x 107(d) x 35(h) mm
6.3″ x 4.2″ x 1.4″
Weight (Gross):0.8 kg (1.8 lbs)


Accessories and design:

The Zen Blue comes well protected in a recyclable white cardboard box. Inside we´ll find accessories such as an RCA cable, a power adapter, bluetooth antenna and the warranty card.

The Zen blue´s design also keeps the characteristic grey metallic finish of the rest of iFi Zen products, if you have tried the Zen Dac, phono or Can you'll know what im talking about. This design is unique and the aluminium finish feels durable so i think it was a good idea to keep the same design for all of the Zen amps and dacs.

In the front of this device we'll find the bluetooth pairing button that also works for waking up the Zen Blue (it sleeps after some minutes when no device is paired). Next to this button there's the bluetooth codec display that changes up to 7 different colours depending on the format and also there's a bluetooth pairing display that will alternate between blue and red colour.

In the back we'll find all the digital (coaxial,optical) and analogue (rca, 4,4) outputs. To choose between these 2 kinds of outputs there's a switch that we'll have to manipulate.


How to use?

The Zen Blue automatically turns on after plugging the 5V adapter, next it will try to pair to any available bluetooth connection. There's no much explanation here, just connect one of the available outputs to your headphone amp, active speaker or dac and enjoy.


Daily use:

The Zen blue is easy to pair to any kind of device, no matter the bluetooth codec it will achieve the correct pairing. It also supports all bluetooth audio formats and uses one of the newest QCC5100 Qualcomm SOc so your only concern here is to use the latest codecs of your phone or PC to achieve the best audio quality.

I used almost daily the Zen blue and it never got warm. The bluetooth connection is very stable, has a very good range and I never experienced loss of signal in normal conditions. One important thing is that the sound quality achieved with the zen blue is directly related to the bluetooth codec used so i highly recommend you to use at least aptx.

For ease of use, the Zen blue remembers previously paired devices so you'll only need to turn on the bluetooth of your phone or tablet and it will connect.



For this description I'm going to base on analogue mode in which the Zen Blue uses a ESS sabre Hyperstream DAC.

Neutrality and cleanness are two words that can be used to describe the sound of this device. Bass is fast and controlled with no extra weight on it so expect a response according to the songs you play. Using the Elemental Watson tube amp adds the bass more weight and a softer impact that benefits pop, rock and rap songs while using the Zen Can the bass feels tighter and with a deeper punch.
Mids are transparent and detailed, voices and instruments have good texture and weight. With amps like Schiit Asgard 3 the midrange feels warmer and there's a notorious improvement in soundstage depth and imaging compared to the tube amp.
Using the Zen Can (4.4mm output) i experienced the best treble performances amongst the 3 amps used for testing purposes. This amp produces clean and energetic high frequencies unlike the smooth representation of the tube amp or the more relaxed treble of Asgard 3 and thanks to the neutrality of the Zen Blue´s sound these differences were very notorious.



I wasn't expecting this kind of sound from a bluetooth device, the Zen Blue made me forget for a moment the regular USB DACs thanks to a solid sound performance and a reliable bluetooth connection. It paired really well with the headphone amplifiers I used and I found no fails or inconvenient on this product.
The latest firmware for zen blue allows you to have the lights off and you can connect to the zen blue from different paired Bluetooth devices without having to put the zen blue in “pairing mode.” Great firmware support from ifi on this device!


Pros: Great sound
Ease of use
Cons: Bluetooth input only
iFi decided to present an unusual combination of Bluetooth streamer and DAC in one. From the outside Zen Blue looks almost the same as already reviewed Zen DAC. It means that the body is completely made of thick aluminium and feels reassuringly sturdy. Front and back plate have brushed finish, while the rest of its curved body is painted gray. Zen Blue doesn’t possess a headphone amp however.

DSC_7103.jpg DSC_7101.jpg

Unusual part comes in when you find out that Bluetooth is the only digital input available on this unit. Yes, you heard it correctly, there is no USB or any other physical way to connect it to the source. Situation is quite different on the output front. There we have digital outputs in the form of optical and coaxial toslink. Integrated DAC makes sure to provide us with two analog outputs: a pair of RCA connectors for single ended connection and a 4.4 mm Pentaconn for balanced outputs.

All major protocols are supported, including aptX, aptX HD, LDAC, AAC and so on. In the heart of analog section we have ESS Sabre Hyperstream DAC chipset.


I hooked Zen Blue to my main system, Cyrus 8vs2 + KEF LS50, and paired it with my smartphone. Pairing was quick and easy. Except different colors on the front of the unit, there’s even a voice telling you that device is paired and what Bluetooth protocol is being used – neat.

Then listening started. I was using local files of different qualities as well as Tidal stream. Zen Blue treated me with very listenable and enjoyable sound. Level of details is respectable and comparable to it’s wired cousin Zen DAC. Sound character differs a little bit though. Whereas Zen DAC offered warmer and almost fluid-like presentation, Zen Blue has a bit leaner approach. Blue’s bass notes sound less weighty but firmer, while midrange is somewhat sharper and more upfront. Vocals sound rich and present through both of the devices. In upper midrange and higher range Blue is favoring details over smoothness. I must say I prefer Zen DAC conically but the difference is not big by any means. On it’s own Zen Blue is quite capable DAC and you want feel lacking on the sound quality front, especially if you like its more upfront approach.


Next thing I was interested in is how good of a Bluetooth streamer Zen Blue really is. For that purpose Topping D50s came in really handy. First of all, it’s a very competent DAC. Secondly, it has an integrated Bluetooth receiver that sounds OK but nothing more.

I’ve connected Blue to D50s using optical cable and started listening. First thing that was immediately noticeable is that D50s has better analog stage than Blue itself can provide. Sound was simply more revealing, with weightier bass notes. Soundstage was deeper and populated with cleaner and better separated tones. I caught myself just browsing through my playlist, enjoying the music instead of taking notes, and that’s always a good sign. Quick switch to D50s internal BT receiver revealed that it is no match for Blue. Sound became mushier and softer. Bass notes were not as deep and punchy while other instruments didn’t have as clean edges and transients. At this moment I started to realize that some of the bad sonic traits I previously assigned to Bluetooth connection were much less obvious with Zen Blue.

This called for further testing and I connected Blue to the best DAC I had at hand – Burson Playmate. Sound coming from this combo was rich and meaty. Again, I found myself in a situation of taking a tour to enjoy the music instead of taking notes for the review. Switching between this setup and Playmate’s USB input finally showed the limits of a Bluetooth connection. As good as it was, music coming through USB had more micro details, leading edges had more byte and upper register was more airy. That said, I wouldn’t notice anything seriously missing in Blue-Playmate setup if I hadn’t made this direct comparison. That good and nicely balanced this wireless combo sound is.



Zen Blue is an interesting device. I think it’s made for those with specific demands. For those that put convenience in front of that last drop of sound fidelity accessible through wires. With its fine sound quality it makes a hell of a case for such a decision too. Its analog outputs are as good as you get in this price range. But by being able to sound this good over digital outputs, Zen Blue qualifies itself as an upgrade for any of you having a really good DAC already but wanting to enrich it with a Bluetooth connectivity.

. . .

You can find this and many other reviews on my website

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Headphoneus Supremus
Pros: Great protocol support and output options, solid build, firmware upgradable.
Cons: May make you eat crow.

disclaimer: The Zen Blue was graciously sent to me by iFi Audio since I have been working on a stream of bluetooth devices. The Blue is one of several models in the Zen line and is a bluetooth streaming device. The other current Zen model is the Zen DAC and while similar in construction, it is strictly a desktop DAC/Amp and does not overlap the bluetooth functionality of the Blue. A big thanks of iFi-Audio. If you are interested in the Zen series or other iFi products, check their website.

Unboxing / Packaging:

The Zen blue ships in a lift top style box with the main unit housed in an egg-crate surround and the antenna, power cable, and RCA cables in a small box to the right of the unit. An instruction card and warranty card round out the package. If you are planning on using the RCA analog output, which is arguably the most common use case, you have everything needed to start using it immediately. If on the other hand, you want to use the digital output, you will need either a coaxial or an optical cable. The cable I most wish was included or at least offered via iFi’s website as an add on is the 4.4 balanced to dual XLR adapters for use with balanced gear. As of this writing, the iFi website does not list any such option. For those interested, I purchased a 4.4 balanced to dual XLR for testing from LQi Cables (I have no affiliation).


The Blue is a sturdy unit with a solid metal shell including the front and rear face-plates. Four screws run the entire depth of the unit and connect the front and rear faceplates. The board is slotted into the case so has no play in any direction when the screws are tightened down. The front face has a button on the left, a large central LED indicator with the iFi logo in the center, and an LED to the right that indicates connection status and pairing. The functions of the LEDs are discussed more in the connectivity session below. The rear face, from left to right, starts with the analog outputs. First the 4.4mm TRRS balanced line-out connector followed by the RCA connectors. The switch for analog or digital output rests between the RCA ports and the coaxial output port. A Toslink optical port is next in the sequence followed by the SMA antenna connector. At the far right, the 5V DC power input rounds out the back. The only thing that seems out of place in the package is the antenna as it does not look to be of the same quality as the main unit, nor does it match with the color scheme of the unit as it is bright white. One could argue that the antenna can be turned parallel with the unit but doing so either obstructs the power port and still sticks out 3 inches past the unit, or blocks all of the outputs except the 4.4 at the far left. I’m sure the antenna is a 3rd party made component and iFi was more concerned with function than aesthetic, but it does call attention to itself with its coloration (see below).


Ok, yes I cheated on the photos and they are iFi stock photos. It saves me taking apart the unit and potentially damaging a component. The main components of the Blue are the Qualcomm 5100 bluetooth chip, and the ESS Sabre DAC. IFi doesn’t mention specifically which chips are in use but the dac is one of the SOC type chips (ES9023, ES9219, or similar) that incorporate the 2Vrms amplifier with the dac chip. The board does not exhibit any identifiable op-amps in the signal path as would typically be seen if the chip were something like the 9018k2m. Likewise I suspect the Qualcomm chip is the QCC5124 as that is the only member of the family that does not support AptX adaptive and the datasheet for the Blue mentions AptX and AptX HD but makes no mention of adaptive. It is entirely possible that I am wrong on the exact model numbers as these are educated guesses based on iFi literature and what I can see in the stock photos.

The only input is Bluetooth with support for AAC, AptX, AptX HD, LDAC, HWA, and the standard SBC. Outputs include both digital and analog options with Coaxial and Optical digital outs and RCA and 4.4 Balanced analog outs. A couple of items worth noting at this point are:

The 4.4 balanced port is a fixed volume Line Out port and should not be used for headphones or earphones as the volume will be extremely high and potential damaging. The balanced port is designed instead for a 4.4 to dual XLR adapter for connection of the Blue to balanced inputs on another device.

There is a switch to the left of center on the rear panel that allows you to choose digital or analog output and only one or the other is active at any given time. Unlike some other models that will simultaneously send to both analog and digital, the Zen Blue is designed for either/or.


The Blue has both visual and auditory prompts for connecting a device so I recommend the following sequence for setting it up.

1.) Choose your output and make sure the selector is in the proper position

2.) Wire your output to your stereo or headphone amplifier and make sure the amplifier is on and you can hear output.

3.) Plug in the wall wart, and then plug the cable into the power port on the Blue itself.

If done in this sequence, you then have the benefit of having both the visual prompts on the front of the unit and the auditory prompts available to you as you pair your devices to the Blue.

At first the right most LED will blink blue. This is searching for previously paired devices. If none are found, the Blue will go into pairing mode and the LED will respond by blinking blue/red. The Blue can also be forced into pairing mode by holding the button down and waiting the LED indicator to flash blue/red before releasing it. The Blue can pair with up to 7 devices so can be switched between tablet and laptop etc without having to re-pair each time you wish to switch devices.

When a device connects to the Blue, the LED will become solid blue, and a visual and auditory prompt will tell the user what protocol is in use. Standard bluetooth connections (SBC) turn the middle LED (iFi Logo) green and are announced as SBC. Connecting an I-pad turns the logo yellow and announces as AAC. Connecting an AptX capable device turns the logo blue and announces APTX while AptX HD turns the indicator bright pink and announces APTXHD. Interestingly, LDAC and HWA are listed as supported by a future firmware update, but connecting my Sony and Motorola devices both announced as LDAC and turned the indicator a Cyan color. HWA should turn the indicator white, but I did not have an HWA enabled device to test with. Once connected and playback begins, the right most LED is used to indicate bit-rate. If the LED is blue during playback the bit-rate is 44 or 48 kHz. If the indicator is white, the source material is either 88 or 96kHz. I was able to do several tests with LDAC and high bit rate files and the Zen did identify all of them correctly. (As a side note anything over 96 is also down-sampled to that when sent via LDAC).

Distance from source to unit was good with nearly 25 meters possible in open space before reception started to drop. Single layer drywall didn’t defeat signal, but multiple layers easily did so source and receiver will likely need to be in the same room although it can be a fairly large room and direct line of sight between devices was not required.


Once paired and the music starts to play, the Blue does a good job of being a transparent conduit between source and amplifier. The typical ESS signature is on display with a slightly thinner, more detailed, and somewhat clinical output. I didn’t find this a problem at all as pairing it with a neutral to slightly warm system works very well and even when pairing it with a neutral system does not make it sound overly thin or sterile. Overall, detail level was quite good, and I was impressed with the quality of the sound when using LDAC and the higher bit rates.


There are lots of Bluetooth devices popping up to fill this space in the market, so where does the Zen Blue fit? I’ve had several of its competitors on my desk of late so here are some take aways from the compares

Xduoo XQ-50 – the least expensive of the bunch at around $59 retail, the XQ-50 is a well made little box, but lacks the style of the Zen and won’t compete in supported protocols either as it does not offer AptX HD, LDAC, or HWA. The XQ-50 can be used as a USB Dac which the Zen Blue cannot, but it is limited to 16/48 so is of limited utility. Also worth noting, the Zen offers balanced output which the Xduoo unit does not. This is a case of you get what you pay for. The Xduoo is a good value, but the Zen packs a lot more features in at only slightly more spend.

The Aventree Oasis Plus falls into the same class as the Xduoo with a retail of $70. Build of the Oasis+ is all plastic vs the Zen’s metal housing and the Oasis+ comes away looking like a toy next to the Zen. The Zen easily outclasses the Oasis+ as it is easier to pair, supports more and newer protocols, and has lower latency. The only point scored for the Oasis+ is that it can be used to transmit as well as receive. Overall, the Zen is simply a better option for those looking to add bluetooth input to an existing system.

Arguably the first two fall into a less expensive class of devices when compared to the Zen Blue. The next compare is on a much more even footing as the Auris BluMe HD retails at $120. The first thing one notices when comparing these two is the difference in size. The BluMe is roughly 1/3 the size of the Zen Blue. The down side is that the BluMe lacks coaxial and balanced output compared to the Zen and has its antenna on the front where it calls attention to itself. The BluMe also uses a micro-usb power input rather than a DC wall-wart. Both units support AptX HD, and AAC, but the BluMe stops there while the Zen Blue adds LDAC and HWA as well. I found both had roughly comparable antenna with no appreciable difference in distance between source and unit before break up became an issue. Unless you just love the diminutive size of the BluMe, the Zen Blue is the better unit.

And lastly, the AudioEngine B1 is the most expensive in this list at $189 retail. Both the B1 and the Blue are solidly built units with the B1 using a micro-USB power input rather than the DC wall wart style of the Blue. Size of the B1 is again considerably smaller than the Zen Blue and like the BluMe, the B1 has its antenna on the front in full view. The B1 has a single button on the front for power/pairing that also serves as the indicator light for pairing and power on. The B1 lacks the indicators for different bit rates that the Blue has, as well as the coaxial and balanced outputs of the Blue. The B1 supports AptX HD and AAC but again lacks the LDAC and HWA support of the Blue. Distance was again roughly comparable when the same protocol was in use.

Thoughts / Conclusion:

Well, I may be forced to admit that Bluetooth has a use case in audio. In its early days, I commented that I thought Bluetooth was an answer searching for a problem and I saw no real drawbacks to having wired headphones or sources that were large enough to accept the decrease in sound quality that came with wireless. Devices like the Zen Blue are forcing me to re-evaluate that position. It looks good, works as advertised and damn if it doesn’t sound good too. Having the ability to stream directly from my Ipad, or LDAC enabled DAP or phone directly to my home system with little loss of sound quality does provide an ease of use that none of the wired options rival. Sure streamers exist, but then you still have to have some form of wireless to control them remotely, and the ability to transfer from your in-ear to your home system and keep listening to the same song from where you left off is kinda nice. If the Zen Blue can make me rethink my position on the need for such a device, it has to have been easy to use, and work very well indeed. I’m sold. I think you will be too if you give it a try. The Zen Blue is a heck of a box for the price.