Introduction

 

 
I would like to thank Tony at HifiHeadphones for this opportunity to join the review tour of the Lotoo PAW5000. The PAW5k was with me for one week and honestly, I wish I had more time with it to properly take advantage of the many features it offers.

 

This review should of course be taken as a grain of salt as it is my opinion and only my opinion. I have past experience with quite a few cans and IEMs before. I personally own or have owned these cans and IEMs (to the best of my knowledge):


 

1. Sennheiser HD25 Aluminium 25th Anniversary Limited Edition
2. Sennheiser HD424
3. M-Audio Q40
4. Denon AH-D2000
5. NAD VISO HP50
6. Aedle VK-1
7. Beyerdynamic DTX-101iE
8. Monster Turbine Pro Gold
9. ADL EH-008
10. Koss Sportapro
11. Other odd vintage cans
12. Flare Audio R2Pro
13. Final Audio Design Heaven VI

 

Aesthetics

Packaging and Accessories

 

I can't say much for the way the Lotoo PAW 5000 arrived as they were sent my way by another reviewer and not the manufacturer or a third-party seller, but when I opened up the package I was greeted with a small box that immediately split into two when I took it out.
 
The top half contained a flat and well-constructed USB 3.0 cable, a neoprene armband and a plastic case which allows the PAW5k to be used with the armband. I didn't have use for any of the latter two as (for the armband and case) I'm a potato who doesn't exercise at all and (for the cable) because I transfer all my music using a MicroSD card.
 
The bottom half contained the warranty and quick-start guide and underneath those, the deceptively small player nestled in black velvet-covered foam. I have to say, this player is presented quite nicely and the packaging seems to be adequate without being excessive.

 

Design and Build

The Lotoo PAW 5000 is a small all-in-one Digital Audio Player (DAP) constructed of what seems to be two metal panels with a plastic middle separating the two. I'm really not worried about the player breaking anytime soon because of its solid construction. It fits really nicely in my hand because of its rounded corners and if anything feels a little heavier than expected.
 
The front consists of the screen, a navigation scroll wheel with a play/pause/ok button in the middle, fast forward and rewind buttons, a music menu button which also allows for Fn functionality with a long press, a back button which also gives access to the setup menu with a long press, a button which accesses the proprietary 'ATE' (Acoustic Timbre Embellisher) and a parametric EQ, and the power button.

 
The left side has the high/low dampening slider, the volume buttons and the high/low gain slider. The right side has a single USB 3.0 port for connection to a PC. The bottom has the MicroSD card slot and the top has a 3.5mm TRS phone out, a 2.5mm TRRS balanced out and a combination line out/optical digital out 3.5mm jack.
 
The scroll wheel feels solid enough when I turn it but the buttons seem to be somewhat wobbly when I attempt to move them. This shouldn't be too much of a problem but for a cool £330 perhaps it leaves a little to be desired. All the buttons are fairly easily accessible but the power button feels just a little awkward to hit using my right hand. This could actually be a design feature to stop people from accidentally pressing it though!
 

Usability

Loading Music and Format Support

Loading music has never been easier for me; I did my typical firmware stability test and loaded my phone's 64GB Micro SD card directly into the DAP without formatting of any kind. Lo and behold, it worked without a hitch! Several other DAPs which I shall not name have hiccuped at this stage, being rather confused with the other files present on the card, but the Lotoo PAW 5000 prevails!
 
I don't personally own any DSD files or much of anything beyond 16/44.1 FLAC. Yes, I'm not a believer, I know. However, for the purposes of this review, I downloaded a few of my father's high-resolution and DSD music and loaded them into the PAW 5000. The DAP ate them without a hitch and gave me music just like with any old 16/44.1 file. The PAW 5000 works well with MP3 and WAV and also appears to accept APE, OGG, M4A, AAC, ALAC and CUE playlists.
 

Screen and UI

 
The screen isn't the biggest, but is more than adequate for a simple DAP. The Lotoo PAW 5000 comes with a rather exotic UI, but fortunately it was very easy to learn how to to use it. It has a rather retro styling which to me is very endearing and unlike anything else on the market and the limited space is managed rather well with all useful information being present on the screen.
 
The UI seems to be very responsive with no noticeable lag whenever I operate the DAP. Scanning the music into the database didn't take long at all either. There was no 5-minute-long wait for me this time like, again, some other DAPs have forced me to undergo. The scroll wheel is a huge asset with larger libraries like the one I have; zipping from A to Z has never been faster with any DAP I have used so far and is only limited by the speed at which you turn the wheel.

It's very easy to access whatever you want to on this device; everything can be done in just a few clicks. However, something that does annoy me is how you can't skip tracks unless you hit that awkwardly-placed power button to first activate the screen. Please do fix this as I'm a user that tends to skip around my music a lot and it took me a while to get used to how the PAW 5000 does things.
 
Another thing that may be an annoyance to some users is how the UI is a file-based one with no support for tags of any kind. I happen to already be a very organized file-based DAP user due to being exposed to the Shozy Alien and it's minimalist UI but people who are used to tag-based UIs will have to spend some time cleaning up their library before being able to use this DAP.
 

Sound

 

Equipment and Burn-in

The equipment I used was:

1. Windows laptop (running Foobar 2000) > Stoner Acoustics UD110V2 > Project Ember with Mullard CV491 > Headphones
2. LG G4 > Cozoy Aegis > IEMs
3. Lotoo PAW 5000 > IEMs
4. Lotoo PAW 5000 > Project Ember with Mullard CV491 > Headphones 

Since this is a review unit, I have no idea how long this DAP was burnt in, so I'll assume that they've already been used for many hours and burn-in is not a factor here.

 

Bass

The first thing which came into my mind was accurate. It was very accurate, rather like studio bass, especially compared to the stronger meatier bass of the Cozoy Aegis. It extends very well, is nicely controlled and is punchy but there's not too much authority in each hit. It's a drier kind of bass, one that purists will enjoy very much but I personally do not find to be the most appealing.

 

Midrange

A nice, transparent yet smooth presentation is best used to describe the mid-range of this DAP. It's on the same level as the Cozoy Aegis but to me is slightly thinner and brighter, especially the upper mid section. It accurately brings forth the timbre of musical instruments but it never gets too strident or sharp. It's also very dynamic and clean and can be quite enjoyable but again, it's slightly too thin for my own tastes.

 

Treble

There's a slight 'digital' feel to the sound which does give the treble section a very detailed response. This, however, also means that it doesn't pair well with brighter sources or badly-mastered music and the Aegis is just that much more natural to me and fits my preferences better. However, it does make the R2Pro sound more neutral than it does out of the Aegis due to this and thus to some people, it may be preferable.

 

Soundstage/Presentation

The soundstage is very accurate, but has a distinct lack of depth that does hinder the overall layering of music and is further emphasized by a lack of blackness in the background. This is fine for less complicated pieces but when you try to force a full orchestra through this DAP these shortcomings becomes very easy to hear. I wouldn't try to play music that's too complicated through this DAP at all.
 

Headphone/Line Out Power

The headphone out is good enough for IEMs and efficient cans but chokes when feeding more inefficient full-sized cans such as the Sennheiser HD650. This is a DAP that is best paired with more portable audio equipment it seems. This isn't necessarily a bad thing though as it means that it won't hiss with the most sensitive of IEMs due to the lower power output.

 

I briefly tried to utilize the line-out of the PAW 5000 and fed the signal into both my Gilmore Lite and Project Ember. Unfortunately, it was beaten by the lowly UD110v2 DAC which has a much smaller price tag, so I have to say that the internal DAC is best paired with the internal amp.

 

EQ and 'ATE'

As mentioned previously, there is a button on the front of this DAP which allows for both a parametric EQ - a very nice touch which not many DAPs I've used so far have - and a propriety DSP-based sound filtering system which Lotoo calls the ATE (Acoustic Timbre Enhancement). Only one can be activated at a time.

 

I didn't try it extensively but there is the option to create custom equalizers as well as the presets. None of the presets or ATE options really appealed to me and I don't really use EQ with my R2Pros as I'm happy with their sound. However, I can see how this will appeal to people who are a fan of extensive EQing of their cans or people who have a problem with a specific part of the sound signature of a pair of cans.
 

Conclusion

 

I've really enjoyed the week I had with this product. Lotoo have really made sure that the end user has a joyful experience from start to end. The UI is incredibly unique and one-of-a-kind and to me has a very cool styling and this is backed up by the power of the SoC which ensures smooth, rapid navigation. Music files are very easily recognized and played and extensive gain, EQ and ATE functionality also allows the user to alter the sound to their liking.
 
However, it’s not without its flaws; a file-based system mean that tag-based users will potentially have to do a lot of work reorganizing their library so they can navigate the PAW 5000 properly. The sound signature, while very good, is also somewhat polarizing and not everyone will enjoy it.
 
A wonderful enjoyable user experience from the moment I open up the box to when I finish listening mean that this product is something that I would happily recommend to someone who enjoys a clean, pure sound signature. 
 

 

Specs

==Introduction==

 
I would like to thank the Head-Fi Massdrop staff and AKG for producing such a good pair of headphones. This pair has honestly been one of the best cures for upgrade-itis I have had in a long while and I think that it will be a nice ending to the long story of the AKG K7-series driver as I think AKG decided to do this because the driver is nearing the end of its life cycle. 

 

This review should of course be taken as a grain of salt as it is my opinion and only my opinion. I have past experience with quite a few cans and IEMs before. I personally own or have owned these cans and IEMs (to the best of my knowledge):


 

1. Sennheiser HD25 Aluminium 25th Anniversary Limited Edition
2. Sennheiser HD424
3. M-Audio Q40
4. Denon AH-D2000
5. NAD VISO HP50
6. Aedle VK-1
7. Beyerdynamic DTX-101iE
8. Monster Turbine Pro Gold
9. ADL EH-008
10. Koss Sportapro
11. Other odd vintage cans

 
As for the backstory behind these cans, I bought the AKG K7xx when I read the description for the drop for it on Massdrop.com touting these pair of cans to basically be a warmer, bassier AKG K702 Annie back around November. As I have already tried various AKG cans in the past and disliked many of them because of the lack of bass, the overly bright tilt and the oh-so-dreadful headband bumps that most of the mid-tier AKG cans seem to possess, I thought to myself that this would be just the ticket to satisfy my desires and jumped right onto the drop, to the displeasure of my wallet and the absolute joy of my ears.

 

==Aesthetics==

Packaging and Accessories

 
These headphones arrived much later in typical Massdrop fashion in a rather typical box with all the usual labelling on it advertising these cans.  (As most people say, you forget that you’ve bought something on Massdrop and then whatever you’ve bought comes as a pleasant surprise much later!) The packaging these headphones come in is, for lack of a better word, minimal – just enough to keep them safe and make them look pretty but nothing else. When I opened it to have a look, the cans seemed to be quite lonely as it comes with absolutely no accessories to accompany it, apart from a ¼-inch adapter. Well, I suppose that means that my attention will be focused on the cans, it seems. I just wish they came with a carrying case.
 

Design and Build

The AKG K7xx Massdrop 1st Edition is a pair of open-backed headphones co-designed by Massdrop and AKG and are the first batch of a limited run of 6000 headphones. For a pair of $200 headphones, they have a fairly typical build for this price point and are mainly made out of plastic with a bit of metal and real leather used for the headband. They obviously won’t survive a direct hit from a nuclear strike but they should last fairly long under daily use. Plastic obviously means that they feel slightly cheaper but this also contributes to its very light 235 grams of mass which is very good comfort-wise (as I will mention later).

 

They have a really cool stealth black colour scheme which deserves props to AKG for completing the cycle of colour schemes they used starting with white for the original AKG K701 and ending with black for this pair of cans. They have a single-entry configuration for its 3m rubber-coated cable which, while nothing special, does the job with fine fashion. One end is terminated in a 3.5mm jack which accepts a 3.5mm to 6.3mm adapter provided by AKG and the other end is terminated with a 3-pin mini-XLR jack. Left and right sides are labelled on the outside of the headband and is fairly easily located. The ear-cups are free to swivel a small amount in any direction but do not fold flat as they are designed for desktop listening.

 

Comfort and Isolation

Firstly, these are open-backed headphones. Therefore, isolation is irrelevant in this review as they let in almost any background sound and thus isn’t fair to properly judge. However, I do have to say that the leakage from this pair of cans is surprisingly minimal considering its nature and I do have to say that I’m impressed.


Comfort, on the other hand, gets a very big thumbs up for me because I tend to be fairly picky when it comes to this. The pads, while not being the deepest, are adequate enough for my ears to nestle in the cups for a few hours without any issues. 

 

The only gripe I have with them is how the tips of my ears touch the inside and how this causes some pain after a few hours, but by then I should be taking a break anyways so this is a fairly minor issue. The headband, like I mentioned previously, is made of real leather, which is a nice touch. The main plus for me, however, is the fact that they have none of the atrociously painful headband bumps that early AKG K7-series headphones had which means that the headband rests comfortably on my head. Clamp is also fairly minimal, being just enough to keep these on my head as long as I don’t start headbanging but not nearly enough to hurt the area around my ears.

 

The only other issue I have is with the elastic headband suspension system. It’s been fine for the few months I’ve been using this pair of headphones but I’m somewhat worried that they’ll lose elasticity over the years (especially since there have been reports of this happening with other AKG cans) but this also means that the entire system is self-adjusting, which is perfect for my OCD self as I just have to put them on without worrying about setting the headband to be exactly this much distance apart.

 

==Sound==

 

Equipment and Burn-in

The equipment I used was: Windows laptop (running Foobar 2000) > AMB Gamma2 > Headamp Gilmore Lite V2, with no EQ used. These headphones have at least a few months of usage and I haven't detected (or don’t remember) any change within the first 100 hours or so of using them. However, I did not burn them in at all and  instead used them straight out of the box.

 

Bass

As this is an open-backed headphone, extension will of course not be as great as a closed-back headphone. However I was pleasantly surprised to hear that these reach surprisingly low with good clarity and texture. There isn’t the biggest amount of bass, but it’s definitely enough for every genre of music I listen to. It’s punchy and quick when it needs to be and never overwhelms the sound signature.

 

When it comes to orchestral pieces, sub bass is extremely important for reproducing the feel of the piece. I’m happy to say that this pair of cans have enough to make for an enjoyable listening experience. Compared to the HD650, the bass is far quicker and actually works for electronic music unlike the HD650.
 

Midrange

The mid-range of these headphones take center stage here. It’s very clear and natural-sounding but also a little warm to give vocals and instruments a little extra oomph to make them sound majestic and lively, unlike most AKG cans in this price range. There isn’t a music piece I’ve listened to that sounds artificial or unnatural with these headphones so far, which greatly impresses me as many other headphones I’ve listened to simply don’t work with specific genres. Everything is articulate and very well-defined and is most similar to a window into the recording. It’s not overly lush and rich but not overly thin and cold either and even subtle distortions in the music can be heard as a result of mastering errors.

 

Treble

This treble can best be described as neutral to slightly bright, like a cool sip of water in a summer’s day. It’s very well-extended, precise and linear with some subtle lower-treble emphasis which is fairly typical of an AKG can. However, this emphasis is far less pronounced than most other AKG cans and for that I am grateful as I am sensitive to nasty treble spikes. It’s also very resolving, able to pick up a lot of detail in recordings and can be described as rather crisp and clear. However, despite the focus on detail of these headphones, the treble never gets too bright as long as the recording is good quality.

 

Soundstage/Presentation

Here we go, the famous AKG soundstage that the company’s headphones are known for having. As expected, the AKG K7xx does not disappoint, offering a spacious, wide, high and deep soundstage with excellent positioning and clarity. Every instrument has its own place and the soundstage is so realistic that oftentimes I will think that a sound in the music came from real life – trust me, it’s a confusing feeling when this happens and it’s a good thing!
 
The overall sound signature of the K7xx is very natural and lifelike. The frequency response for the most part seems to be fairly neutral and most importantly, natural. This pair of cans especially excels with live recordings but can handle most any genre you throw at it and brings the focus of the listener, not the sound signature of the AKG K7xx like some headphones do. Timbre and tonal balance is both excellent and overall these pair of cans seem to be somewhat like a pair of speakers. This also means that they are not forgiving of poor-quality source files which can be a good or bad thing depending on your choice of music.
 

Update: The Bass Port Mod

After doing the fairly simplistic bass port mod (the details of which are detailed here), the bass quantity improved by a noticeable amount without bleeding into the mids. They're now an excellent pair of cans for even those genres which require a heavy-handed approach to the bass section while still being great at what they were originally good at. Anyways, I like these cans even more now, but keep in mind that the mod is not for everyone, especially not for those who prefer a linear bass section.


 

==Conclusion==

 
The AKG K7xx is probably the best $200 (excluding the $30 shipping) purchase of my life so far. I have been happy with them for over 6 months and I am sure I will be happy with them for many years to come. I prefer it over a lot of the other headphones I’ve auditioned, including its fellow brethren, the Beyer cans, the Sennheiser HD650 and many more. The value is simply insane and I think that its AKG’s best value pair of cans they’ve made in a while.

 

Some things that AKG could improve on, although I don't see much, is to perhaps include a carrying case for these wonderful headphones as it would be a shame if they broke. I would also love it if they used a 4-pin XLR instead of a 3-pin XLR connector for the cable. It's a good thing that they cost only $200 though as this helps to justify the lack of accessories. However, the bass port being closed up is in my opinion a strange decision. I have a feeling that AKG planned to leave the port open but closed it up at a later time for whatever reason, the likes of which completely defeat my mind as I greatly prefer these cans with the port open.

 

 

==Specs==

---

Introduction

---

Here I am with another amp review and this time, its of the Portaphile 627 MICRO with the stock OPA627s.

Keep in mind that absolutely everything in this review is subject to the law of Your Mileage May Vary. A head's up, as this is going to be much longer than my other review as I had far more to test it with so here's a tl;dr. 
Now that I've gotten that over with, time to continue. I just managed to catch the pre-order discount of US$439 including shipping (hurrayzaroo, US$100 off!) and I gotta say, its worth every cent I paid for it. I would've even been happy to buy it at the normal $539 price (if I didn't know about the preorder price as I'm rather cheap) as it's just so good at its job.
 
I paired it with just about every pair of headphones and IEMs I had on hand and some that I got to audition at joebloggs' shop (thanks for the opportunity btw NLNH). I also compared it with the Apex Glacier with certain cans. The cans that I have paired with the Apex Glacier (and can therefore compare the sound quality of both amps) are asterisked in the below list. The list is also split into the categories of portable headphones, desktop headphones, IEMs and the HD424 2000Ω version (he's a special one). Both amps were paired with the DX50 using my ZY HiFi mini to mini. 
 
UPDATE (5/4/14): me and my dad had a mass listening session with all our headphones on 4/4/14, so I have updated some of the headphone impressions. I've also realized that I made out the Glacier to be worse than it really is - it is still an extremely good amp.

---

Everything Else

---

As I had been in England for boarding school and had the amp sent to Hong Kong to avoid import tax, I didn't have a chance to unbox the amp as my audiophile dad did that task for me. Therefore, he was the one who had the honour of listening to this amazing package first. He reports that it sounded amazing paired with his DX50 and HD650 but was too dark when paired with the HD25 ALU (opinion revised 5/4/14, please check below). As I actually appreciate a dark sound (I have the VK-1 after all), this was a great first impression for me and I couldn't wait to personally try it out.
 
This thing came packaged in what looks like the kind of box eggs come in, which I understand as it's an effective cost-cutting measure to do such a thing. It charges via a mini USB port on the back of the headphones. Apparently they require a lot of power input as Cesar included a double usb to mini usb cable. 
 
I was handed the amp by my dad before I got into the car in the way home and I was greeted by a solid hunk of metal with a potentiometer sticking out the side. Boy, was I impressed. Although the build refinement is nowhere near the excellence of the Apex Glacier's, the Glacier's unmatched in its class and the 627 MICRO impressed in a different way. While I was worried about scratching the Glacier's finish (and its scratched anyways), I had a feeling that the 627 MICRO might be the Nokia of amps in that it's finished slightly roughly but feels indestructible despite its size.
 
This amp does have two levels of gain (+2dB and +7dB with the OPA 627); but with all of the cans I auditioned it with, even the HD424, only the lower level was needed as its so powerful and I achieved listenable levels. I did not detect any noticeable sound differences between low and high gain, nor did I detect any channel imbalance or hiss in any of the headphones or IEMs I auditioned at my typical listening levels so that's another +1 for this amp.
 
When I paired the amp with the DX50 and VK-1 and turned it on, I was greeted...by a very loud click. Ouch. This immediately taught me the habit of turning on the amp BEFORE plugging my headphones in. When I wanted to switch with the Apex Glacier and turned off the 627 MICRO, I was greeted...by another very loud click. Ouch x2. This immediately taught me the habit of turning off the amp AFTER unplugging my headphones.
 
Finally, when it ran out of juice 5 minutes from my house as my dad did not charge it enough (4-hour battery life yay), I was greeted...by you guessed it, a third loud click. Ouch x3. Needless to say, I was a bit annoyed but after looking up the amp on the computer, I was greeted with similar reports of people experiencing the same thing. Well then, looks like I have to live with the clicks. I'm willing to put up with them though as the rest of the amp is just so amazing.
 
(UPDATE 5/4/14): I forgot to describe the size of the amp compared to other gears. It is, of course, thicker than the Glacier. However, when factoring in the potentiometer, it literally stacks perfectly with the DX50. It's like a match made in heaven when seen from above or below. This is another +1 in my book as it makes the already stiff potentiometer even harder to turn which means there's a lesser chance that I'll get a nasty volume-related surprise when I use the combination when out and about.

---

The Sound With Portable Headphones

---

After getting over the initial shock of the loud click, I started playing Hotel California, which is my typical reference track for, well, pretty much everything. Well, colour me impressed; this amp is small, but the sound it produces is so amazing that I couldn't quite believe my ears at first. Dynamics, bass extension, treble extension, mids presentation...everything about the amp's sound trumped the Glacier's when I played Hotel California. The 627 MICRO just sounded like a far superior, more refined amp when compared to the Glacier.
 
When I switched to the Q40 and listened to Shadows by Lindsey Stirling, I noticed that the bass just doesn't hit quite as hard as the Glacier and therefore this amp isn't quite as good with electronic genres of music where the music isn't nearly as complicated and bass quality and presentation is the most important. However, the bass is still of an extremely high quality and I would still be perfectly happy to have this amp over the Glacier as the Glacier is only slightly better.
 
(UPDATE 5/4/14): I finally bothered to try the HD25 ALU with the 627 MICRO. Man, it's another good pairing with the MICRO. I think that I can safely make the assumption that most headphones will at least sound decent with the MICRO and at most sound absolutely amazing. In addition, I no longer feel that the MICRO lacks bass. Rather, its just the right amount of bass for the song being played, as both the HD25 and Q40 have a good amount of low-end present when I played Lindsey Stirling's Shadows - my dad thought there was too much, but I can be a bit of a basshead at times. Of course, mid and treble frequencies were both represented in all their glory - the violin sounded like a violin (actually a very important aspect of presenting the music as the violin is one of her unique selling points for her music!) and everything was layered correctly.

---

The Sound With Desktop Headphones

---

On Sunday the 30th of March, I went to joebloggs' shop to audition a few cans. There, I had the simply wonderful opportunity of auditioning the HD800, W1000x, Kaiser 10 and DITA Answer.
 
I personally still found the HD800 to be a bit too bright with the 627 MICRO, which was the same impression that I got when I listened to it with the Glacier a while back. However, it was a much better pairing than the Glacier was as I listened the entire length of Hotel California when paired with the 627 MICRO whereas I took the HD800 off within 20 seconds of Hotel California when I used the Glacier. I also heard the famous HD800 soundstage in all its wonder, well-represented and layered in all its magnificence when powered by the 627 MICRO.
 
The W1000 on the other hand was a simply magical combination with the 627 MICRO. I listened to three and a half songs in a row before I reluctantly took it off to leave the shop as my dad had something he needed to do. Hotel California, Cherry Star from Hibi No Uta, So Far Away from Dire Straits and half of Rain Musique from the Symphonic Rain Vocal Album, Rainbow. The sound was simply so smooth and effortless that I forgot about the fact that my dad had to leave every time he reminded me. I was rewarded with ouch x4 as I had forgotten my newly learned 2nd habit and switched the amp off without unplugging or taking off the headphones.
 
The HD650 was already a great-sounding headphone when my dad and I paired it with the Glacier but it was simply taken to another level with the 627 MICRO. Again, the Glacier was trumped in every which way and the little distortion I detected when using the Glacier with the HD650 disappeared completely. It's a shame I find the HD650 to be uncomfortable as that detracted from the overall experience of listening to the music and probably made the combination sound worse than it really was.
 
(UPDATE 5/4/14): I've got another opinion on the 627 MICRO VS the Glacier on the HD650. Although I felt that the Glacier was trumped by the 627 MICRO, my dad felt the opposite. He said that the Glacier sounded more detailed when playing Hotel California while I felt that it sounded more pleasant with the MICRO. We both came to the conclusion that the MICRO was more 'analogue' and the Glacier more 'Digital', with both having extremely positive connotations. Also, I can safely say that our differing preferences were caused by individual sound signature preferences as I prefer a darker sound to he does - he really doesn't like the Aedle VK-1.

---

The Sound With IEMs

---

Remember what I previously said about the bass of the 627 MICRO not being as hard-hitting as the Glacier's? Well, when I used The Answer, I got bass, and plenty of it. Not to say that its a basshead IEM though, as the other frequencies were represented very well. This was also an excellent pairing and by then I've gotten the impression that the 627 MICRO can pair at least decently with everything and still get amazing results. Once again, Hotel California was well-represented 
 
The Kaiser 10 was the ultimate test of hiss and channel imbalance and I'm happy to report that, as previously said, neither were present. Short impressions here as I don't quite remember how it sounded but from what I remember NLNH saying, the CIEM version is far superior to the IEM version which is a bit of a shame as I can't afford 1/10 the price of the K10 CIEM.

---

The Sound With The HD424

---

Well then, a 2000Ω pair of headphones. Does the Glacier power it properly? Very much nope-ity nope nope. It sounds strident and thin with bad bass texture and overly fatiguing treble. The sign of an underpowered headphone. How do I know? Well, does the 627 MICRO do the HD424 justice? Very much yes-ity yes yes. Compared to when its powered with the Glacier, the HD424 is much fuller and actually sounds fairly neutral now. Bass is still rather lacking but quality is excellent.
 
The sound sort of reminds me of the NAD VISO HP50 except its much harder to drive, cheaper and far more comfortable to me. Also, its coming from a headphone made 40+ years ago. Wonderful! I listened to it for a couple hours without any issue but I replaced the pads with Technics RP DH-1200 pads which were more comfortable to me than the stock HD424 pads. To me, this slightly increased the bass quantity but did not really affect either the treble or mids too much.

---

Pictures

---

This amp was my first audiophile amplifier purchase, bought second-hand off Midnightwalker. I wanted a neutral-sounding amp with an integrated DAC for convenience which would allow me to use it both as a desktop amp/dac and as part of a portable rig. I used this with the MacBook Air using the integrated DAC at a desktop and am currently using it with the Aedle VK-1 and M-Audio Q40, paired with the DX50 and a ZY HiFi audio cable while on the go, having previously paired it with the HD25 ALU and the NAD HP50. I have also tried driving the HD650 with these and comparing with the C&C BH2 and the DX50 in-built amp.
 
First impressions when I opened up the box were that the build of the amp was outstanding. It is made using a kind of raw metal (I forgot exactly what) entirely different from the usual anodized coating which gives it a unique flavour. The face-plates are made using a thicker layer of metal and the writing, although having heard rumors that they rub off, are still entirely visible even after 4 months of frequent usage. It also feels solid and has a nice heft that makes me feel confident in the amp's build quality, and I have not been disappointed.
 
The digital attenuator is another unique feature that I find very convenient. Pressing it turns the amp on and off while moving it to either side changes the volume, while also changing the colour of the LED (oooooooo flashy). The volume the amp was previously set to is remembered the next time the amp is again turned on which I as a lazy person find extremely convenient. However, I am aware other people find this way of changing the volume imprecise as the volume steps may be too large for some people.
 
This amp has three levels of gain. The standard level of gain (+10db) is enough for most cans, but it can be increased to a monstrous +20db or reduced to +0db for very sensitive IEMs. After all, this amp was designed to run with IEMs. I find myself using the standard level of gain for all my cans, but when testing the HD650 I find that I needed to increase the gain to compensate for the increased input impedance of the cans. However, changing the gain requires a thin sharp tool which can be difficult to do in a portable setting. A simple toothpick is enough to change the gain setting.
 
Using the HD25 ALU, I felt that the amp is very true to the source. It makes good files sound amazingly pure and accurate while making bad files bite into your ears with an ice-cold chill. This also means that it is very neutral and unforgiving. It is almost like a wire with gain in that the amp will barely change the sound produced. Each headphone connected to the Glacier has its own unique sound. The HD-25 ALU is lively and with plenty of PRaT, the HP50 is natural with its famous roomfeel effect audible in full effect, the VK-1 is dark, impactful and smooth while the Q40 is bass-emphasized with neutral mids and highs. A little PRaT is injected into the music, giving it a sort of liveliness that is reminiscent of the HD25/grado effect. I find this makes the VK-1 sound amazing with vocals and instrumental tracks and the Q40 with more electronic-oriented tracks.
 
However, the neutrality and unforgiving nature of the amp can be a bad thing too, as when paired with the HD25 ALU any flaws in the recording are immediately made apparent. It may perhaps be a slightly too analytical combination to some people. The Aedle VK-1, being a can with very respectable technicalities, suffers in the same way in that flaws in recordings are audible in all their glory. In the same way, when paired with the HP50, I found the bass quantity to be lacking, almost like the AKG K550, although the quality was still outstanding.
 
When connecting the Macbook Air, due to the UAC-1 standard, using the inbuild DAC was completely painless. It is practically plug-in and play and has great synergy with the amp section. However, the DAC very occasionally malfunctions but TTVJ has implemented a handy reset switch in the case this happens which resets the microprocessor, solving all problems. However as with the gain switch, a toothpick or other sharp tool is required to press this switch
 
Overall, I am very satisfied with this amp and I do not regret this purchase at all. However, there are some small nitpicks with the DAC section and the usability of the gain and reset switches that do not hinder overall usability.

Paired with the VK-1

Paired with the HP50.

Paired with the MacBook Air using the internal DAC.