Intro

So yeah, finally I was able to sit down, gather my thoughts and write what's below. Xonar Essence III is a very special product for me. Reason behind this statement is simple: it was able to replace one particular device I was very attached to over last two years or so. For now I won't write down what's the name of brick that had to go, but it had to and that's a fact. Xonar Essence III got me a bit closer to the sound I always liked to hear, cost no object wise. In the long run I'm aiming at AMR DP-777 or Aqua Audio La Scala. Yup, big toys, and they have some things in common, both in terms of sound and build. NOS multibit d/a converters and tubes? It has to be good if you ask me. I've heard stage four Lampizator more than two years ago, and got hooked up. Device internally built like that is my way out, for now I'm fooling myself that having one of those similarily designed bricks I'll be finally able to stop DAC searches and focus on some serious class A monos. Not that NuForce RE9 V3SE I use are bad or something. 
Anyway, Xonar Essence III arrived, and as I wrote, it got me a bit closer to two things I'm really after these days; smoothnes and as much organic presentation as possible. Both are something plainly obvious when multibits and tubes are on the table. I'm into audio long enough to know that's my Holy Grail. Soundwise, smoothness, organic, natural and lifelike presentation is a big thing in my book. And when it comes down to Asus - also novelty. Those aspects of sound were beyond reach in products of that company (and many other as well) thus far. And yes, I've heard each and every DAC and soundcard Asus has in portfolio. I'm not saying that desktop solutions of that particular manufacturer aren't musical. Yet, certain level, or intensity if you will, of sound aspects I've mentioned above are reserved for far more expensive devices. And when I'm talking expensive, I mean Auralic Vega or PS Audio DirectStreamDAC. But that's another story, and another step in delivering me what I want to hear.
 
My first contact with Essence III model was in December 2013. And it has been with me ever since. Polish Asus folks were kind enough to let me use it when the device wasn't needed. And since very little people are interested in and capable of reviewing that kind of equipment, it was with me almost constantly over last couple months. So I got lots of time to know it, and compare to other devices. Because I don't want to overwhelm you guys with too much of a lecture, I'll try to keep the crucial parts as short as possible.
 
Two, scratch that, three disclaimers before we go:
1. I hadn't payed for Xonar Essence III, it was delivered to me as a free sample, no journalistic surprises or secrets here. It came directly from Asus HQ.
 
2. I'm not affiliated with companies mentioned in this article in neither financial, nor personal way. Though, obviously, I know PR people working there, but we get along only on professional level and that's it. To be honest, lady from polish Asus crew helped me to get things done.
 
3. Sorry about my language skills, I'm aware that they could use some improvement. But I honestly believe that by writing stuff such as this review I'll get better. If you consider yourself as a language purist and are afraid your eyes might fall off, please stop reading here. 
 
List of music I used is quite vast: Nine Inch Nails, Bat For Lashes, Rebecca Pidgeon, Einsturzende Neubauten, Corvus Corax, The Knife, Fever Ray, early albums of Mike Oldfield, Filter, Wardruna, Pig, Ministry, Michael Goddard/Monteverdi, Dead Can Dance, KMFDM, Jarboe, Muse, David Lynch, Therion and some Chesky's stuff to name a few. No additional details are needed here, but if someone asks about specific tracks, I'll gladly answer. 
 

Thoughts about build quality

I won't wirte about materials used in Xonar Essence III, as this is commonly known thing. What I can do is to tell you guys what I think about it overall. To make it short, to me Xonar Essence III isn't quite "there" yet. The reasoning is simple: many  devices similarily priced to Asus flagship are a tad better on this particular field. More on that below. I'm almost certain that one or two persons agree with me here, and most of you know what I'm talking about. Metal chasis is nothing wrong, as I don't demand CNC milled aluminum, which is the best possible thing in my eyes btw. But when getting into big league you have to act like a pro, as competition is fierce. There's no room for cutting corners there.
 
 
For instance, I don't like plastic knobs in Essence III model. Badly. Even though those are OK in terms of practical use, they feel cheap. I know it's a small detail, but I often use them and it always strikes me that they are what they are. And after those several months of having Xonar Essence III, those got a bit loose. Also, I'm not a huge fan of mini-XLR's. Yes, they do look nice, and yes, they work as they should. But I had to reterminate some of my cables in order to test the brick after all. I've found some XLR to mini-XLR wires inside of the box, but the bigger ends were male, hence no use of them anyway. It's a manufacturer mistake if you'll ask me. I'm aware that this might be quickly reterminated, so this fairly sad story has its end fairly quickly, but for the sake of the facts I needed to share this with you. Another thing that doesn't rock my boat is front plate. From pure aesthetic point of view, and I consider myself as a person who pays attention to slightest details, that kind of finish doesn't go nicely with the rest. But please bear in mind it's one of those subjective things to point out. I don't see them as a flaw of the product. My guess is that Asus devs decided to use brushed aluminum plate just because rest of Essence models have them as well. It's about somewhat visual integrity of whole "family". Yet, In my eyes Xonar Essence III is something way different in comparison to other models Asus has in portfolio. Therefore and in my opinion devs shouldn't stick to previous, less expensive Essence devices so much in terms of presentation. In the end and judging solely by its looks, for me Xonar Essence III doesn't look and isn't externally built like a $1500+ device. $1000-ish? Maybe, but nothing above that. I just don't feel that build quality. Then again, it's a kind of subjective thing to write.    
 
 
Some people say that volume bypass in Essence III is awkward, for me it works like a charm. It just gets job done, no surprises here. Also, two volume knobs is a good thing to have purely from usability point of view. At least for me, as I often switch between my speakers and heapdones. Buttons are enjoyably clicky and work as they should. Yet, switching between inputs takes some time, more than usual, and I'd appreciate if it could be faster in the future. Though it's fair to write that I got used to each and every "not so good" apect of Xonar Essence III I've mentioned above. Those things aren't dealbreakers by all means, I live with them every day, sound quality rewards them, but we'll get to that in a moment. Xonar Essence III is also well made under the hood. Clean job so to speak, nice components, some more popular than other, but I have nothing negative to write here. I did some op-amp rolling in the very beginning, but shortly I returned to stock ones, those proved themselves to be that good to my ears. The rest (d/a conversion, capacitors, USB reciever, power supplym, TXCO clocks etc.) is known to you guys so I'll skip that part. 
 

Sound

Right, now it's time to reveal which device Xonar Essence III replaced: NuForce DAC-9. It's noticeably cheaper device, but really, really good soundwise. The price difference between them is in my eyes justified and simple to explain. Asus product has much more complex headphone amplifier, and I believe that's the key here. HPO in DAC-9 is just for the sake of functionality of that device, nothing more. NuForce flagship d/a converter is designed to work as a source mainly, and I'm sure everyone is now aware of that fact. Anyway, when I compared line-outs in DAC-9 and Essence III models, I used the same amplification and device. I connected them to JKSPDIF MK3. Then I used 2x NuForce REF9 V3SE monos and KEF LS50 monitors. Cabling was my all time favourite Forza AudioWorks happy family. Onto the good stuff we go now.
 
 
The sound quality of both d/a converters is on similar level overall, but they do some things differently. Essence III model is more polite, organic and smoothest sounding one. DAC-9 is more vigorous device, it presents lows in more punchy way, they go a bit deeper as well. Yet, DAC-9 bass has more rigid texturing and is a bit more hearable in his mid and high sections. I don't like midbass hump, but for KEF's LS50 it works like a charm. Onto mids we go. Both devices have them similar in terms of quantity and texture. But for the second time the biggest difference between the bricks comes into play - Essence III is much more smoother sounding device, more enjoyable in the long run, at least with rest of the setup I use on a daily basis. Detailing and resolution are again on par, amount of high frequencies is also comparable. But then again, Asus device has them more smooth, and audibly more extended. I'm not sure about typical listener, but for me that smoothness and effortless presentation is something I'm after. That's why DAC-9 had to go. And when I look in the past, that brick wasn't considered by me as a harsh, or clinically precise device. DAC-9 in comparison with many products sounds a bit analogue. But Essence III has that kind of presentation on another, obviously higher level. At least to my ears.
 
 
Headphone amplifier in Xonar Essence III demanded another approach. I paired this DAC with Audio-GD Phoenix via balanced cabling. To be honest, HD 800 are amplification demanding monsters, but quality is the case here, they need special treatment in order to get maximum possible synergy. Hence use of Phoenix, it's a kind of obvious and not so expensive choice to make when someone owns HD 800. For some people Audio-Gd amp sounds neutral, for me it's a bit dark, and it's most definitly darker than HPO in Xonar Essence III. Phoenix is on some fields better; lows have better dynamics and go deeper for example. Essence III on the other hand has them more round, softer and polite overall. Does this resemble the story with line-outs above to you guys? It should. Phoenix sounds more precise and resolving. Essence III pumps up mids a bit, this device makes them sound fuller, meatier. It's not that its opponent sounds thin, nothing like that. It's just HD 800 will accept any kind of fullnes with open arms, they need it in my opinion. Yes, that meatiness HPO in Essence III offers is connected directly with a bit weaker detailing and resolution. But it sounds musical, and I'm all for it when it comes down to my favourite headphones. Essence III has more highs, but that's kinda obvious thing to write, Phoenix tends to recess them a bit. But both devices are very good on that particular field, nothing sparks, no razorblades near my eardrums what so ever. Let me just say, that in the end I've sold my phoenix. Even though Essence III HPO isn't as good on technical wise, it delivers. At least with HD 800 and headphones alike. I've tried LCD-2 as well, but it wasn't good neither with Phoenix, nor with Essence III HPO. Too big veil there, but that's not a surprise. LCD-2 need special, transparent and painfully punchy treatment to sound good IMO, and Essence III is about smoothness and metiness more than anything else. And this device does it very well.
 

To sum things up

So yes, considering all things above, in the end I'm more than happy. That's true that Asus could have done some things a bit better. And yes, Xonar Essence III has a hell of a competition on the market these days, real sharks swimming nearby. But one thing I know: do not make mistake of discrediting that device because of its non-audiopphile roots and "parents". Besides in $1000+ price range I believe that it all comes down to sound preferences and synergies more than anything else. And here, my friends, Xonar Essence III shines, especially for me and people equipped similary. I'm HD 800 and LS50 junkie after all. Hence, with Xonar Essence III I have synergy I need to enjoy my music. Although my road is nowere near the end, this device showed me, that I actually can get satisfying smoothness without going madly after excellent Auralic Vega and similarily priced devices. So for now Essence III model works like a charm, and it's a keeper.
 
 
If someone asks me for how long it'll stay with me, I have 100% accurate answer already. I'll switch my sources when AMR DP-777SE is available. But let's not forget it's a $5000 brick. It's an obvious step up for me, but it's also three times more expensive than Xonar Essence III. That's the jump I'm going to make, but till then, I'm perfectly happy in the place I'm currently standing. Oh yes, and one fact needs to be brought up. I listen to PS Audio DirectStreamDAC loaner lately and I love this device. Not as much as AMR DP-777 but still it's a very strong feeling between me and this DAC. It's been with me for couple weeks now. I'll have to send it back very soon. In order not to be shocked, I've put into my setup Essence III again. The result? No big deal, that device still delivers. And that particular experience showed me clearly how good it actually is sound wise. Yes, I could go DirectStreamDAC or Vega right away, money is not an issue here. But instead I'm waiting and I'm having a blast with Essence III. Ain't that something?
 
 

Bottom line:

If anyone asks me whether he/she should or should not consider Asus flagship seriously having $1500 on hand, I'll just say: "Yes, go for it, try it, you have my blessing". No doubt here. Asus guys learn fast how audiophile market works and what it needs these days, so I'm waiting impatiently for their next big move. They know what they're doing and I'm sure we'll be surprised by them more than once in the future.

I'm going to skip parts about build quality and UI of DX90, as lots of words have already been written about those aspects of that DAP. After switching form HM-901 it seems more than OK for me. And even though DX90 isn't perfect usability wise, I've found it quite enjoyable to use when I'm on the go. What I can do is to tell you guys how my adventure with that device looked like.
 
At first, DX90 came into my hands and at that time I had "only" HM-901 nearby. But when my boss ordered me to write review of ten audiophile DAP-s, I had opportunity to compare them all with DX90. In that publication there were MA9, X3, X5, DX50, DX90 obviously, HM-901, HM-802, HM-700, AK120 and AK240. To make it short, iBasso has nothing to be ashamed in comparison to nearly all of those devices. Yes, AK240 is above everything these days in many aspects IMO, but AK120 - not really, I've foud that this DAP is very comparable to DX90 sound and UI wise. And price difference between them? Well, staggering. That's all I can say.
 
In my opinion, the best price-performance factor of all those players belongs to DX90, and HM-700. In terms of pure SQ I'd put DX90 below AK240 and HM-901, on par with AK120, and above all other DAP-s. You can agree with that or say, that I'm over my head. But the fact is that I've listened every hi-end DAP out there on the market, except DX100, I own many of them. And I just am very impressed about what iBasso guys did for mere 400$. That's amazing.
 
Two, scratch that, three disclaimers before we go:
 
1. I've payed for DX90 full amount, no free samples this time for me, no journalistic surprises or secrets here.
 
2. I'm not affiliated with companies mentioned in this article in neither financial, nor personal way. Though, obviously, I know PR people working there, but we get along only on professional level and that's it.
 
3. Sorry about my language skills, I'm aware that they could use some improvement. But I honestly believe that by writing stuff such as this review I'll get better. If you consider yourself as a language purist and are afraid your eyes might fall off, please stop reading here. 
 
List of music I used is quite vast: Nine Inch Nails, Bat For Lashes, Rebecca Pidgeon, Einsturzende Neubauten, Corvus Corax, The Knife, Fever Ray, early albums of Mike Oldfield, Filter, Wardruna, Pig, Ministry, Michael Goddard/Monteverdi, Dead Can Dance, KMFDM, Jarboe, Muse, David Lynch, Therion and some Chesky's stuff to name a few. No additional details are needed here, but if someone asks about specific tracks, I'll gladly answer.
 
DX90 (FW 2.0.0) vs HM-901
 
OK, it's time for the good stuff. I'm not going to write DX90 comparison to all big models out there, I'll just focus on differences with HM-901 on the other hand. It's couple times more expensive, so it'll do just fine. In my test I've used RE-600 and Heir Audio 8.A. In the very beginning it's fair to say that DX90 and HM-901 have almost nothing in common, even though their DAC-s are somewhat similar. But the fact is, that if DX90 turns out to be somewhat comparable to HiFiMAN-s flagship, then value of this DAP will be obvious.
 
Another thing worth mentioning is that compared DAP-s have different sound signatures, so it's another obvious thing to write that if some headphones, IEM-s or CIEM-s will go nicely with DX90, they don't have to with HM-901 and vice versa. To be honest, my 8.A go better with HM-901. They are thick sounding, with lots of bass, and HiFiMAN-s flagship keeps them tight sounding, precise, punchy as hell, detailed and very organic. In comparison to DX90, HM-901 has more punchy lows all the way, from sub levels to kick bass. To be honest I don't think that I'll hear more power in that FR in any other DAP, I just can't imagine that. HM-901 has midbass hump, and I believe that this makes lows so powerful overall. So logical thing is that DX90 has that parts of FR more polite and without any midbass emphasis, which is normaly a good thing in my book. But bear in mind that DX90 sounds very, very punchy as well, it has excellent dynamics, to my ears better than AK120. To be honest, HM-901 is a king on that particular field, and to fall a bit short in a fight with a king is not a shame. Not to me. DX90 is second best I've heard thus far in that regard. And I've heard a lot. Dynamics and punchness are the very first things listener notices with this DAP. Both compared devices have excellent low end overall, very well controlled from A to Z, tight and enjoyable all the way, but different.
 
Midrange is also presented differently by both DAP-s. But in that regard they do sound as a reference to me. Presentation is clear, natural, smooth and effortless, everything is top notch there. For me that smoothness divides "OK" DAP-s from the ones that are excellent. Guitar parts played by HM-901 have a bit fuller body, and they do sound a bit more clear. DX90 is not too far off, the same instruments sound more relaxed, calm. HM-901 has also more highs, but both devices have them smooth and clean, no sharpness at all. At lest not with music I usually listen to. Though one thing deserves mentioning: DX90 is more forgivable for badly recorded tracks.
 
DX90 is bigger in terms of soundstage on both levels: width and depth, though main differences are heard in the center of the show. In some recordings DX90 withdraws vocals a bit too much for my taste, HM-901 has them ocasionally too close, so they're even And don't get me wrong, I don't think bigger soundstage is better one. HM-901 is more aggressive and direct DAP overall and it has more body here and there. So his close presentation to the listener is something logical for me. But it's also more airy and DX90 has not only bigger, but also thicker soundstage. Therefore apples and oranges, lads. Both devices have that aspect very natural, organic and coherent. Even though DX90 is darker sounding DAP, it's equally detailed.
 
Final words 
 
To make it short, iBasso delivered us a monster. DX90 is hands down the best price-performance DAP for me now, and one of the best DAP-s SQ wise overall. This brick has huge potential, and I'm sure even iBasso guys are surprised by how well it sounds. For 400$ it's a steal. If you're into that sound signature, grab one DX90 for yourself, you won't regret it.
 
_________________________________________________________________________________
Cheers,
00L
 

A way too long intro

A while ago good people from Questyle provided me with two devices. Among them is excellent  headphone amplifier - CMA800R. I've been fiddling with it for a while now, and at this point I'm 100% certain that my Audio-Gd Phoenix will be sold without looking back, not even a flinch. Yes, to my ears CMA800R is that good, but first things first. I've bought Phoenix during its FOTM era. It was one of the most obvious choices for me back then, as I'm a happy HD 800 owner. Some of you might remember what people wrote on Head-fi.org about connection of those two. Lots of folks were extremly enthusiastic with the outcome, including me. This combo gave me happiness for couple years, but now Phoenix has to go, there's simply no point in keeping it. Don't get me wrong, that heavy and hot brick has its own unique charm etc, I like it and it's fair to say that I got really attached to sound it provides. I've never had any issues with this amp as well and it did fine job as a preamp. Even though it adds lots of stuff to the sound overall, it's fairly dark and laid back so to speak, and that's hearable.
So there I was, constantly convinced that Sennheiser flagships and Kingwas device delivered me generous amount of musical goodness. Then somewhat unexpectedly HPA-21 appeared, and my audio life has changed. A lot. If Phoenix was able to show me a bit of musical heaven from some distance, Bakoons small box opened those gates of paradise unexpectedly widely and kindly let me inside, at the same time delivering oh so much joy to my ears. That's the best amp for HD 800 I've heard thus far, period. Aye, I'm aware that it costs nearly three times as much as Phoenix, but still fact is a fact, my Audio-Gd device was significantly outperformed, backstabbed silently, deftly and quickly. The stuff HPA-21 does to HD 800 is incredible, this pair is for me the best example of how far synergy can actually go in audio, probably some of you lucky owners of those witnessed it as well. Capabilities of Senns drivers aside, it's a no-brainer that secret of all this "magic" would be batteries in HPA-21 and its signal transmission in current domain all the way. Yes, for me this device is like a chest with very valuable treasure inside. It delivers perfectly linear sound to my ears, yet unexpectedly enjoyable, with very generous amount of smoothness, excellent bass and dynamics which can make my head literally explode. That's about it. Unfortunately my Bakoon loaner had to be sent back and I really miss him. But now I get chills just at a thought that there was a point where I wanted to part with my HD 800. Bad idea, now I know that. They can sound wonderfull. Onto Questyle we go.
CMA800R came along with Q192. Obviously I've started with first one. But before I even unpacked the box I already had enormously huge expectations regarding that piece. If you ask me why, project86's review explains it quite clearly. But for those of you who missed his article I have some fairly simple technical stuff, which goes like this: in Questyle and Bakoon products signal is converted (or not - see SATRI-LINK) to current form and then amplified, that is the similarity between them and those two companies are unique because of that. Thanks to their discrete current circuits they offer a kind of new technical aproach to the case, correct me if I'm wrong but unseen earlier in headphones world. But there are some differences between their products as well, the first firm relies on voltage inputs and outputs, the second one has them as well, but also additional pair of current BNC sockets, those are a part of greater good called SATRI-LINK. But bear in mind that now it's not possible to complete 100% Bakoonish headphone rig and benefit from purely current BNC connections, Bakoon doesn't have d/a converter on the market...yet. But my guess is that we'll soon see DAC with SATRI output and the mystery will be solved, brand fanboys will triumph with their fully current mode rigs fasster than we think. But you get the point, the patch is ready, just waiting in line to be applied to rest of the family.
So logically Bakoon devices are all about current signal transmission from one device to another, to minimalize deformation of the signal along the way. CMA800R is "only" about amplification of it in current form, as I wrote it has voltage in&out, but there's a purpose behind this - better match with other devices operating on voltage signal. Questyle doesn't have a SATRI alike connections available, they didn't go that road knowingly. Anyway, Bakoon HPA-21 does THE trick mainly thanks to its SATRI-IC discrete module, and since Questyle has somewhat similar solution, at least to some degree in amplifier stage, again no-brainer here, I expected the same goodnes after connecting HD 800 to CMA800R as it was present with HPA-21. Long story is short: I recieved much more than I wished for. It's hard for me to say now how close that amp is to HPA-21 pure SQ wise. I hadn't had them at the same time regretfully. But as my memory serves me well, Questyle flagship does very similar things to Senns, that vast synergy appeared once more. Smoothness, punchy lows and excellent dynamics were on the table again... and for 1499$. That really made my day. When it comes down to this particular set of cans, in my book that kind of money spent on extremly well matched amp is a bargain. It's hard to disagree, as we all know that letting go 2500 $ or more for HD 800 matched brick isn't such a big deal, as those cans deserve that kind of money investment... if it will blow our heads with its synergy in the end. They can deliver generous amount of musical nirvana, we all know that. LCD-2 is no exception though, CMA800R as a very linear amp has what it takes to show their potential as well. One of my journalist colegues, after hearing LCD-3 paired with Bakoon was stunned, not to mention he's used to way more pricier devices than HPA-21. Anyway, based on my experience it came to me that HD 800 and current amplification were meant for each other. I don't know, maybe it's just a coincidence. Time will tell as more current based devices will afloat in time, and I'm sure they will. Until then we have what we have, but I'm certain that Questyle and Bakoon are a few steps ahead of the competitors. Products they both provide are very unique to me. Small boxes, big sound all the way, period.
And then, after taking it slow with CMA800R and enjoying it as much as I can, time has come to meet his smaller brother with WM8740 DAC onboard. Again my expectations were high as hell, I already knew that Q192 shares the same tasty amplification circuit, which sits in Questyle's flagship. And back then I also knew what CMA800R can deliver. So before listening period with Q192 it came to me that integrated solution below 700$ price point, that could synergize with HD 800 on similar level than much pricier amplifiers... would be a killer deal. Yet again something really worth taking into consideration by those of you lucky Senns owners, who have fairly small budget to spend. And here's what happened: it delivered. But before we go there, some clarifications are needed here.
 
Two, scratch that, three disclaimers before we go:
 
1. I hadn't payed for any of those amps, they were delivered to me as a free samples, no journalistic surprises or secrets here. Both came directly from Questyle HQ
 
2. I'm not affiliated with companies mentioned in this article in neither financial, nor personal way. Though, obviously, I know PR people working there, but we get along only on professional level and that's it.
 
3. Sorry about my language skills, I'm aware that they could use some improvement. But I honestly believe that by writing stuff such as this review I'll get better. If you consider yourself as a language purist and are afraid your eyes might fall off, please stop reading here. 
 
List of music I used is quite vast: Nine Inch Nails, Bat For Lashes, Rebecca Pidgeon, Einsturzende Neubauten, Corvus Corax, The Knife, Fever Ray, early albums of Mike Oldfield, Filter, Wardruna, Pig, Ministry, Michael Goddard/Monteverdi, Dead Can Dance, KMFDM, Jarboe, Muse, David Lynch, Therion and some Chesky's stuff to name a few. No additional details are needed here, but if someone asks about specific tracks, I'll gladly answer. 
 
 

Build Quality

I should start with stating what kind of product Q192 actually is. That's a single-ended, unbalanced amplifier and DAC combo in one, visually appealing package, at least to my eyes. Judging solely by external build of Q192 it is very similar product to CMA800R, there's no way denying it. Obviously it's a smaller device, but it really looks like youger brother of that excellent amp, pictures don't lie. Because of fairly compact size it sits great on desks somewhere near laptop or stationary PC. Q192 has different proportions in comparison to CMA800R, it's much narrower, but also longer and height wise almost equal. Build quality of those two products is also similar, Q192 front is made out of solid and thick CNC machined aluminum brick. Nicely done, clean and symmetrical job there, no reason to be unsatisfied. I consider myself as a person paying much attention to looks of rigs I'm using, those are seen by me as a furniture as well. Q192 can easily be shown to people without shame on my face. Fun fact: when I look at Xonar Essence III I get irritated. It is beyond my understanding (and I really am forgivable person) why that expensive device is so poorly made, visuals and materials wise. And we're talking about 2000$+ price point here. Plastic volume knobs? C'mon, that's a serious letdown. Asus needs to learn couple new tricks in the future, because looks of their flagship are one of its major flaw. Though tech junkies are also complaining about lack of discrete solutions in Asus audio stuff, for lots of them op-amps are a no-go. Anyway, to me Q192 is way nicer, more clean and minimalistic, and about four times cheaper. How about that.
Q192 chasis is entirely aluminum, it's a two piece set. Top cover is U-shaped, it sits in the oposite one with electronics mounted on it (also in the shape of U letter) thanks to rails and four screws on top. Damn, again those screws, this could be done better, those pesky little creatures disfigure that clean and nice look efficiently, they really do. But there is a chance this will be done better in the future, I've talked to Questyle owner, and he was very open minded person in that regard. I suggested removing those screws, he said they'll think about it and that's fair enough for me. I had some other advices as well, i.e. black colouring as an option. But my point is he saw that some improvements can be done, he had his eyes and ears open to clues I provided and that kind of attitude has much appreciation from me. Not to mention Questyle team response time is great, and their language... there's no such thing as language barrier. I'm not sure if you're aware, but that's often serious trouble in contacts with Korean or Chineese folks, I could easily name ten brands which have huge problems on that particular field. But since I'm such a nice guy, I won't go down that road. OK, enough off topics, getting back on track.
Q192 front panel is fairly simple. In cavity with small rake perfectly cut around it aluminum volume knob has been placed centrically, it works really good; fluently and lightly. Though I have to admit that the same element from CMA800R is better in that regard. It's perceptibly more resistive and always plced in the middle regardless of its position. What I have on my mind is that in Q192 bigger brother the gap between volume knob and front of the case remains the same all time. The one in Q192 isn't that perfect, but still very good and I have nothing to complain here, I wrote those things just for sake of the facts. On the right side of the front panel there's one 6,3 mm voltage out. The rake around it is cut with care, so yeah, CNC job well done again. On the left, near volume knob there's a small LED diode, it gives fairly subdued blue light when the device is on, it matches the casing nicely. A bit further there are two switches; one selects USB or Coaxial inputs and second one fixes line-out to 2 Vrms. All good here. On the back of Q192 there's IEC socket, 2 x Coax (one in and one out), 1 x USB type B socket and a pair of RCA's, those are line-outs mentioned earlier. Aye, Q192 is unbalanced, it's a kind of "it has all you need" package, so no surprises there. Though I'd like to see line-in there as well, just for those of you who would like to use DAC better than WM8740 onboard. But again, I understand that Q192 is for people just starting their headphone adventure as well, a kind of potentialy one solution that would be with them for years. And since Q192 delivers, that's quite possible.
As for internals, we have standard stuff here, at least to some point. A pair of OP275's is in preamplifier stage, those serve as a low pass filters. Another two - OPA627's - sits in headphone circuit. DAC chip is well known and liked, Wolfsons WM8740. Though I value them less than Sabres, not to mention multibit Burr-Browns. But Q192 is fairly budget solution, so that particular Wolfson is a safe and price adequate choice to make, not to mention it's DSD capable. No complains here from my side. And in Questyle's flagship - CAS192 (2000$+ balanced d/a converter), there's also WM8740 so I guess it's not wise to despise those or, to put it nice and simple - judge book by its cover. S/PDIF reciever in Q192 is WM8805. This device has asynchronous USB input and ES1304 branded processor dedicated to it. What it does remained unclear to me, but Questyle CEO explained that this is actually a memory chip. There are three clocks nearby as well. One deals with 44.1 kHz family, second one has 48 kHz on him. I hadn't got a clue what third does. My guess was that one of them is double, and that's probably a way to deal with jitter more efficiently or something like that. But those were only my assumptions. Truth is different though, third clock is responsible for communication control with PC, it is so to avoid PLL circuit loop, as this would bring phase noise to the table. But the most important stuff in Q192 is, at least for me, current amplification circuit mounted onboard, this is the place where magic happens. This section has couple stages. First is VCCS (Voltage Control Current Source), which is equivalent of Bakoons SATRI-IC, to some degree of course. After signal beeing transferred there it is converted to current form, then it goes to Ai section, which amplifies it. Next step is I/V conversion, OPT and then non-positive feedback to stabilize it. That's it. Fairly simple, but it cost Questyle engineers couple years of hard work and many iterations of that design. But my ears are telling me that every day spent in the labs by those people sure was worth it. No doubt about it. Truth be told, thus far I hadn't heard amp that would get along better with HD 800 in Q192 price point. OK, onto tasty parts now.
 

Sound Quality

To make it more challenging I used Xonar Essence III in my tests. OK, I hadn't got any other integrated solution below 1000$ on hand as well, so you get the point. There was also DAC-9 from NuForce, though it hasn't been used much lately. The target for me was to check how good both stages of Q192 are: amplifier and DAC separately. To achieve that I've used RCA's, as obviously Q192 doesn't have XLR's. HD 800 and LCD-2's were my picks of the day, no surprises here as well. And, of course, CMA800R was there too, just to see differences between Questyle babies, to witness how good amplifier circuit in Q192 actually is. I try not to complicate my life as often as I can, so to achieve that I simply connected CMA800R to Q192 line-out. Just a little volume tweaking to mach both HP-outs... and that's it: one DAC and two amplifiers were ready and willing to be compared, nice and simple. FIX in preamplifier stage of cheaper device was of course on. Seeing how good WM8740 DAC actually is was a bit more tricky. I've used Audiobyte Hydra-X as a source. That excellent, yet pricy S/PDIF converter was connected to Q192 and Xonar Essence III coaxial inputs alternately. From there Phoenix was used as main amp, and headphones mentioned earlier in the end of that road, but that's not all. After tests of DAC with headphones I used NuForce REF 9 V3SE and a nice pair of KEF's LS50 monitors, those were very handy this time, equally revealing regarding Q192's WM8740 capabilities. And using Audiobytes S/PDIF converter showed me how good USB in Q192 is as well. I hope this testing procedure is understandable, it won't get any harder, I promise.
DAC test went as first one. Q192 had very hard task as Xonar Essence III is couple times more expensive. And to make it short, Q192 lost this battle. New flagship from Asus delivers more refined and smooth sound, that smoothness is its key feature, at least for me. Not to mention, that HD 800 will engage with any portion of that stuff with huge smiles on their ring radiators. They do sound good when they sound smooth, but not in a polite way and that's what Essence III does to them. Also Q192 has more closer and smaller soundstage, especially in front of the listener. Overall this device doesn't sound as refined as competitor. "The Third" has a tad more width, but the differences in depth are more audible. Though I have to admit that Q192 doesn't kill what's best in HD 800, oh no, amplifier section does the trick nicely, but we'll get to that in a second. And again I have to bring smoothness to the table. To me Xonar Essence III is the smoothest one out there for me, I'm quite sure I haven't heard any other DAC that would combine that aspect with very generous portion of details in such a good way. To be honest I regret that I hadn't any alternate device nearby to compare with Q192. Hence different reviews of this Questyle product might be a bit more revealing regarding its DAC section. So yeah, sorry for any inconvinience. Now onto amplifier we go. To make it short it would be sufficient enough to write, that in that regard Q192 has lots of that goodness slumbering in CMA800R. And that, fellow Head-Fi'ers, means that this integrated solution is really, really good. Up to the point, where if I had to choose between Essence III's balanced amplifier section and the one in Q192, without any doubt I'd pick the second. How about that. So it's 1:1. But to be just, loosing in some aspects to three times more expensive device isn't a shocker.
Current circuit mounted in this "Q" thing provides, again, very generous amount of dynamics, smoothness and linearity. And yes, when matched with HD 800 we have a sound so enjoyable it's hard... errr.... not to simply enjoy it. That's the stuff I really hoped Q192 will deliver, and it had, all the way. OK, about that linear sound, it's a bit tricky. When using Senns flagship I've noticed audible bass boost, this was going on in both Questyle products I have. Don't get me wrong, this is a good thing, as Senns do need a bit of something extra down there. But with LCD-2's nothing like that happened. Yes, their bass was wonderful as well, but I've found it to be as generous as usual, no new dB's here, but tighter and more punchy, again, as usual if my memory seves me well. Awkward, I'd say, but current domain is full of surprises I guess. Ah, and yes, while using Audeze "entry" planars the difference between Phoenix and Q192 was more than just slightly audible. Yes, I'm aware that LCD-2 and Phoenix isn't a kind of happy marriage, but you get the idea. OK, let's move on. Now I could use magnifying glass and write about each aspect of what I've heard. But to make it short I'll just add that CMA800R in comparison to Q192 sounds more lively, with better low ends, blacker background, wider soundstage and overall more detailed presentation. Though subtle, those differences are audible. I'm sure they will deepen over time, but for now, after taking price into consideration, well, Q192 has nothing to be ashamed of, quite the opposite in fact. It stands beside his bigger brother, not in his shadow. And for the sake of the facts, I'm pretty sure that better sounding DAC would do to some additional good things to Q192 amplifier circuit, that we could witness improvement there. But since that device doesn't have line-in, it's off the table. 
 

Final Words

I'm very impressed. I didn't think that Senns HD 800 can sound so good when connected to device that cost less than 700$ . Not more than a year ago I was convinced that SQ wise it is not possible. I've tested many headphone amplifiers and to my ears HD 800 performed extremly well only with Bakoon HPA-21 and Questyle CMA800R thus far. Now I have to be just here, Q192 is in that group as well. Yes, it's below SQ level of those two, but huge synergy with HD 800 is once more on the table, I believe that similarly priced Q192 competitors are far behind in that regard, no matter if it's NuForce, Matrix, Asus or Cambridge. And, again, there's that lovely, justified price on top of that. Current amplification shines again and I'm very happy about that fact. I'm now really confident, I know I am, to the point that I can easily state that if someone after reading my review will buy Q192 to match his HD 800, I know he'll be overall very, very happy person, believe it or not. You can thank me later.
As for DAC, well, things do complicate here a bit. Q192 does really fine job, but not as extraordinary one as amp section. It's solid in that regard. But I'm quite sure some devices from direct Q192 competitors, and of course in its price range, can perform better on some fields. But to be honest, we're judging "full package" here, as Q192 is integrated solution, ain't it? So it's all about its overall capabilities, the final effect rather than only some parts of it. And loosing to Xonar Essence III won't put Questyle 700$ DAC into infamy, as Asus has something very, very good there. And yes, Q192 has ASIO and asynchronous USB, therefore it will make life a bit sweeter for those of you, who pay attention to those things. Q192 lacks in that regard only DSD support, but these days it's not an issue... yet. That kind of files is still exotics, to put it gently. Though it isn't a surprise that Questyle will add native DSD playback in their stuff, so good news indeed. Just heard this will happen to CAS192, so I'm sure Q192 will have that too, as I wrote WM8740 is DSD capable after all. 
 
Bottom line:
 
After taking all things I wrote above into consideration I have very short and sweet finishing lines for you: just bear in mind, that if you're after some great, yet affordable integrated solution to match mainly your HD 800, look no further, Q192 will deliver lots of joy to your ears, and I'm deadly serious now. You'll be surprised how well this thing performs with that particular set of cans, but similar goodness will occur with LCD-2 as well. And that's it, short and simple. In the end I can only say, that in my crystal ball I see very colorful future for Questyle. Those guys really know how to handle "things", their products are world class performers both price and SQ wise, beyond reach of the competition with obvious headphones, at least that's what my ears are telling me for couple weeks now. Current domain owns and addicts, you have been warned.
 
 

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P.S. If anyone is interested, below there are some product photos I did. They were published somewhere else, but I'm the owner of those.

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Hi, My name is Dawid and I'm an audio junkie. I'd like to share about Astell&Kern AK120, HiFiMAN HM-901 and Monster Audio MA9.
 
Just for sake of the facts: I'm a audio journalist by profession, I work for polish press. Usually I stick to polish sites and paper magazines. But Head-fi.org is one of those portals I visit every day, constantly for couple years now. So far I've been stalker here, and figured it's time to finally write something, share a thought or two with this community. I've read lots of great reviews here, which were inspiration for me. Currawong, project86, ClieOS and some other folks are my personal heroes. Well, I believe that mainly thanks to Head-fi.org I'm doing audio journalism for a living. So there you have it, blame is on you guys, sorry
 
Anyway, my starting point was portable audio, I remember the day when I bought my first serious IEM-s - Westone 3. Jumping from Creative EP-630 straight to those three BA driver devils was a significant experience in my audio adventure. Then, there came RockBoxed X5L, DIYMod along with RSA p-51, fancy cables and so on. You get the point, I knew it was a good start for me, we all begin somewhere and portable stuff is quite affordable way to go. I quickly moved from that kind of equipment towards desktop setups. HD 800 have appeared, then Audeze LCD-2, Audio-GD Phoenix, NuForce DAC-9, some S/PDIF converters, one from John Kenny, and lots of other various equipment. I hadn't got much time to enjoy those, KEF LS50 were bought shortly after completion of my headphone rig. A pair of NuForce REF 9 V3SE and Xonar Essence III were nice addition to those speakers. Then came some additional cabling, anti vibrating platform and couple other things that could improve what I already had at home and office. Well, people here aren't joking when they welcome newbie person by saying... we all know what. Yes, that part about beeing sorry for that poor mans wallet. It's the most accurate and sincere greeting I've ever read anywhere. As Tony Soprano said: "what can you do?" Yeah, sorry wallet, I'm aware you hate me.
 
Slight hint here: for those of you looking for a pair of extremly good, yet fairly affordable bookshelf monitors I strongly suggest taking a good, long look on those KEF-s. Once those are in your posession, you won't look back with regret, trust me. In terms of overal SQ and build quality, that particular KEF anniversary item is ridiculously low priced. Uni-Q's in LS50 create UNBELIEVABLE space in front of you. OK, I've made my point, now getting back on track.
I've been extremely happy with my KEF + HD 800/LCD-2 rigs for a while now and I seriously thought that my adventure with portable audio will be only occasional from now on, or even that'll go into hiatus. Truth be told, old habits die hard, full circle has been staggered. Once again my journalistic curiosity won, and as a result review samples of FiiO X3 and iBasso DX50 were sent to me. Next in line were Monster Audio MA9, HiFiMAN HM-901 and Astell&Kern AK120. It still surprises me that I am so heatedly chasing "it", not too long ago I thought that DYIMod + p-51 combo will be the only portable thing I'll ever need. Obviously I was wrong again, oh well, joys of beeing typical audio junkie. My personal tale ends here, yet it gives start to another.
 
If someone got offended by my personal touches in "lovely" background story above, my apologies. I'm unknown here, so I figured it'd be nice to write few words about myself.
 
Anyway, this "fairly short" review is about three DAP-s: MA9, HM-901 and AK120. I had all of them at the same time and I thought it'd be nice to share my findings and observations. Lots of words were written on this forum about each, so I don't think I'll surprise you guys with anything new and shocking. Since those are portable, during listening period I used Heir Audio 8.A CIEM-s along with Forza AudioWorks Hybrid Series wiring and HiFiMAN RE600. I could go with something more analytically sounding, mainly to match fairly dark and thick sound signature (or deadly neutral to some of you) of MA9, but it is what it is. I could have used HD 800 or something similar as well, but I believe that most of us are using DAP-s with much smaller in-ear products. And AFAIK there's been lots of informations regarding drive capabilities of those flagship players. But that isn't the case here, I'm going to focus mainly on build quality, UI aspects and sound comparison. Some opinions below are purely subjective, you'll see soon enough, you've been warned.
 
List of music I used is quite vast: Nine Inch Nails, Bat For Lashes, Rebecca Pidgeon, Einsturzende Neubauten, Corvus Corax, The Knife, Fever Ray, early albums of Mike Oldfield, Filter, Wardruna, Pig, Ministry, Michael Goddard/Monteverdi, Dead Can Dance, KMFDM, Jarboe, Muse, David Lynch, Therion and some Chesky's stuff to name a few. No additional details are needed here, but if someone asks about specific tracks, I'll gladly answer.      
 
Two, scratch that, three disclaimers before we go:
 
1. I hadn't payed for any of those DAP-s, they were delivered to me as a free samples, no journalistic surprises or secrets here. MA9 came straight from Monster Audio HQ, HM-901 from HiFiMAN HQ, and AK120 - from polish distributor of iriver, as policy of that korean company is a bit different when it comes down to sending samples to the press.
 
2. I'm not affiliated with companies mentioned in this article in neither financial, nor personal way. Though, obviously, I know PR people working there, but we get along only on professional level and that's it.
 
3. Sorry about my language skills, I'm aware that they could use some improvement. But I honestly believe that by writing stuff such as this review I'll get better. If you consider yourself as a language purist and are afraid your eyes might fall off, please stop reading here.

 
Again, a lot of stuff has already been written about build quality of each DAP I'm discussing here. Their inputs and outputs are known, the same story is with displays, used materials, external memory usage and so on, I have nothing particulary new to add here. The same thing is with SQ. But I'd like to share my personal, somewhat subjective feelings about each of that portable beasts.
 
Build Quality
 
Astell&Kern AK120 is the smallest unit. It surprises me how tiny it actually is when compared to its rivals. That DAP is very well made. If I'm not mistaken, for a couple of days now we have a chance to buy titanium version. AK120 is pretty comfortable device to use, at least when compared to its competition and it's as solid in real life as it looks on the pictures. CNC machined aluminum chasis feels very luxurious, the device sits in pocket or on hand without any discomfort. I'd preffer it to be more taller and a bit narrower, but nothing dealbreaking for me here. AK120 thickness is very good, again I have nothing to complain. And there's that lovely volume knob, excellent job here, far better in comparison to AK100, which I also had for a short period. I've found that element in AK100 to be too loose. It's not that it has problems with volume adjustments, because from what I witnessed it doesn't. But I constantly had this feeling that one day it will just fall off, no matter how solid it actually is. AK120 doesn't have that problem in my book, it's more stable, and thanks to two aluminum and curvy convexities nearby it's more robust and better looking IMO. AK120 screen is OK, but that's it. We all know that devices like this DAP are SQ oriented, but it still is a bit of a problem for me after using one of popular and fairly new smartphones and jumping onto you know what. There, I've said it out loud.
MA9 is different beast. It's huge. No, it's not huge, it's HUGE, that's more like it. This DAP is built like a tank. If I'll ever encounter some shady type in dark alley with serious need of robbery and I'll have MA9 in my pocket, it will be most definitly used to defend myself, it's no joke. And when the guy is down on the ground, he'll have his face burned. Aye, MA9 is extremly hot, at least sample I received. Its CNC machined aluminum body acts like a radiator, so no surprises here, and most of weigh of that DAP is its batteries, those are the main source of its temperature. During summer I could really feel MA9 in my pocket. Though this device has no problems in beeing constantly hot, it won't burn your trousers, which is a good thing, and it's stable when RockBoxed. But the fact is stil a fact: it's the hottest one I've used thus far and nothing can change this. MA9 not only looks like a brick, but acts like one on hand. I wish it could be more round here and there. Chasis of this device isn't too thick, I took a peek inside, there's a generous amount of electronics inside, mainly two huge batteries, therefore not much can be done here. But I have fairly small hands and outdoor usage was a bit problematic for me. To be honest, there's a huge gap in that regard between MA9 and AK120, the second one is a winner all the way. Though I love the robustness of Monster Audio flagship, its buttons are excellent, again good word to describe them is "robust", and overall quality of this DAP is top notch. Its fairly small display isn't something I'm not used to, in my eyes they all are alike. But I'd be extremly happy to see something better in the future. I'd say that MA9 in terms of build quality and looks has a character, it's not for everyone.
Last one, HM-901, is a bit smaller and lighter than MA9, and obviously still bigger than AK120. HiFiMAN's flagship is in my book on the last place among all three DAP-s when it comes down purely to quality of used materials, attachment to details and so on. I've tested lots of HiFiMAN products, and I know most of them sounds really good, but build quality and looks, well, you know where I'm getting with this: competition does this stuff better. HM-901 is also robust device, and I witnessed its shockproof abilities couple times, it fell on the ground more than twice, yet it always remained unscrateched and in 100% operational. But on hand, well... plastic, no matter the quality of it, isn't something as good as aluminum or other fancy stuff. It's safe to say that HM-901 is very expensive DAP and I really would like to see some improvements in terms of looks (a bit more minimalistic chasis wouldn't hurt) and used materials. Nothing dealbreaking but you get the point. Its screen does the job poorly in sunlight and, correct me if I'm wrong, nothing can be done about that, at least for now, as brightness level implemented in its OS is very limited. Truth be told, I got used to that disadvantage, but any improvement on that field will get a big hug from me. Navigation wheel has its issues as well, it's not as fluent as it was in the beginning of my daily usage of HM-901, which is a bit odd as I thought it'll get better over time, more loose and in conclusion easier to operate. I hope you'll understand me now, but rubbing level of the wheel isn't equal, there are some spots where its resistance is more sensible than in others. Same story is with silver volume knob of that DAP. There'a also additional "issue" with that part as well, it's recessed. I get the point behind it beeing not so easily available, sudden increase of volume is impossible, we all know that, and that's what Fang Bian wanted to achieve, it's for our protection. But from my point of view I can't increase or decrease volume level using only one hand and that's something I'd like to do quite often, HM-901 competitors allow that with ease. OK, if I try hard enough it's doable, but far from comfortable, you get the point. One thing needs to be mentioned here as well: channels matching is excellent, I have to give it to HM-901. Though steppes are audible (this occurred with all three amplifier cards I have), I'd like to see something between fourth and fifth as those are volume levels I usualy use. Once again, things I've mentioned could use some improvements in the future, but I don't consider them as a dealbreakers or major flaws, I can easily live with them. HM-901 is, at least for me, better device than MA9 in terms of outdoor usage, mainly thanks to being a bit thinner and more round with unregular shapes here and there, it sits in my hand more comfortable. And it's not nearly as hot as Monster Audio flagship. I'd say HM-901 is pretty cool, even with balanced amplifier card onboard and that's a big plus for me.
Bottom line - Buid Quality:
 
In terms of daily usage AK120 does really nice job, competitors are way, way back. That device can be easily operated by only one hand, it's small and very well made. So AK120 is my number one here, HM-901 is the second, and not too far behind - MA9. Looks are very subjective, I don't want to even go there. But if someone would be burning my face with hot iron and demanding my confession in this regard, I'd say that AK120 has gold again, MA9 is not too far away, and HM-901 gets last place.
 
User Interface
 
To make it simple: all three devices fall short when compared to RockBoxed DYIMod. I'm a die hard fan of that soft, I can't help it. It's perfect for me, it has everything I need. That's why jumping from RockBox to anything else is usually a pain for me, when that happens I feel like a small kid left alone deep in dark and scary woods. That's true, I'm afraid of anything else. To be honest, if DAP can't be RockBoxed, it has to be really good at everything else if it'd like to be my primary source on the go. Of course sound quality is my main point of interest when we're talking about flagships, but second is software, build quality comes as third. Buggy OS is a potential dealbreaker for me. OK, now that we got that sorted, tasty bits ahead. I won't go into three separate paragraphs for each device mentioned in this review, not too much to say here. AK120 holds its ground fairly firmly. Touchscreen is a matter of taste, though. IMO it became way too popular thanks to smartphones era, but I don't need it as a portable audio enthusiast. I'd go for physical buttons anyway, those are more reliable for me, and DX50 or Astell&Kern OS is not nearly as good as the one in SGS III or iPhone, that's a fact, it's hard to argue with that. I hadn't got a chance to fiddle with DX100, but I'm guessing it represents somewhat similar level to two DAP-s mentioned above in terms of screen responsivness and such, therefore still nothing groundbreaking for me. Again, jumping from iPhone to DX50 and other touchscreen based DAP-s is quite painful experience for me and I know that some of you will sympathize here as well. Anyway, AK120 has its issues, my main point is that its navigation isn't as fluent as I'd like it to be, i.e. browsing files list is laggy. I'm not sure if this can be fixed in the future OS updates, I'm guessing that guys from iRiver are limited by AK120 internals in that regard. From my point of view overall usage of that DAP is quite good, but I see room for improvements. We all saw FiiO X5 OS smoothness recently, that's something I'd like to see in touchscreen based portable players as well, for future flagships it's a must in my book, we all get used to good stuff quite easily, don't we? HM-901 could use LOTS of improvements as well i.e. I miss clickwheel sound from my DYIMod, I always had it on, subtle and quiet, but it was constantly on. But that's a small issue. The bigger one is overall slowness, responsiveness of physical buttons and inability to adjust wheel speed. I'm aware that guys from HiFiMAN want to create their products from A to Z in their labs, but my guess is that 99% of us would be in 7th heaven if we could exchange current HM-901 OS to RockBox, I really hope it will happen one day. I don't want to be monothematic, but yes, in my case it's about RockBox again. And that's what guys from Monster Audio did. Standard OS on their devices is, to put it as simple as I can, unusable for me. The one put onto HM-901 is at least stable, I can't say that about MA9. Often crashes, not reliable battery lifetime indicator and so on are major disfunctions for me. But that aside, MA9 has RockBox, which works as it should. And that's the solution to all my problems, this is enviroment well known to me, which I like, couldn't be better, I couldn't be happier. It's very fast, MA9 turns on in couple seconds. No matter how fast I'm going with buttons of that DAP... there's no lag. Nothing much to add here.  
Bottom Line - User Interface:
 
MA9 has it. When RockBoxed, it's a great DAP, unique on many levels. Competition is, at least in my eyes, far behind. AK120 is second, because even though I see screen tearing while browsing files list fast, touchscreen is responsive on acceptable level. And HM-901 is last one. But IF MA9 couldn't have been RockBoxed, it would be on last place.
 
Sound Quality
 
And we're getting to the end and most tasty parts. Again, lots of words were written about AK120 and HM-901, a bit less about MA9. On this forum I see, that people favor HiFiMAN's SQ more than AK120, other things aside. And to make it short and simple I agree, HM-901 sonds better for me too. MA9 is different beast, but we'll get to that in a moment. For those of you, who do not like to read much this will do:
 
HM-901 is king of dynamics, yet it has very refined sound signature, AK120 sounds smoother and more polite overall when compared to HiFiMAN's flagship, and MA9 is the most laid back and dark of all three. There. Folks starving for details should read on. But bear in mind that I won't go deeply into each players sound signature, I believe all of you here already know which one plays in what  way. I'll focus on the differences between them and, in the end, how they affect me. Onwards we go then.
 
HM-901 is the most dynamic one out there, this player literally makes my blood boil. It also is the most forward sounding DAP, with the best lows overall. Those are very, very punchy and, to my ears, they have a slight midbass hump when compared to other devices. I usually don't like it to be boosted in any way, as I'm very "boominess sensitive" person, but with HM-901 nothing bad is happening in that department, quite the opposite in fact. Bass of that DAP has also a bit more stiff texturing, or not as round as competition, in that regard it is on one side of the spectrum, MA9 is on the other (with the least amount of it as well), and AK120 sits somewhere in the middle. But again, HM-901-s bass has the best dynamics and goes lowest. As for midrange, I've found HM-901 and AK120 to be somewhat similar here in terms of temperature, the second has mids maybe a tad warmer. MA9 has them the most neutral, those might be seen as a bit dark. But all three products are very good here; natural, dynamic and detailed, I have only good things to write here. For some time I thought that HiFiMAN's DAP has mids a bit more forward and direct sounding when compared to other devices, and to some degree I see them that way. But it came to me that it's all about their soundstage placement, we'll get to that in a second. HM-901 has similar amount of highs as AK120 and sounds a bit brighter here, MA9 is behind in that regard when compared to competitors, we all know why. For those of you who do not, here's short explanation: MA9 DAC, PCM1704, tends to have them a bit rolled-off. For some people that kind of presentation is seen as the most accurate one, to others - as a roll-off and I'll leave you with that. I can only say that my ears are telling me that MA9 sounds excellent in that regard, no matther what. Now onto the soundstage stuff, things are getting a bit hairy here. Overall, AK120 is excellent in that regard, such tiny DAP, so amazing spaciousness, kudos. HM-901 is a bit smaller on that field, I have depth on my mind here, mids are more closer to listener and that's why this device sounds more direct to me. Those aren't huge differences, yet noticeable, at least that's what my ears were telling me during my listening period. AK120 soundstage is very wide and deep, lots of layers there. HM-901 also is extremly good on that field, but since midrange is more closer to the listener, well, you get the point. As for MA9, the amout of air in soundstage of this DAP is enormous, overall imaging and depth is top notch, but that's not all. I don't know if I can describe it properly, but the way musicians are placed one next to another, the richness of the whole show... magic. Soundstage of MA9 has even more layering than AK120, at least that's the way I see it. Monster Audio flagship delivers such scenical realism, that I see no competiton on the market for that device in this regard, and I've heard a lot of DAP-s. Of course there might be an amp which would do better with AK120 or HM-901, but when we're talking about playing straight from headphone-out... nope, at least not to me.
Bottom line - Sound Quality:
 
It's just a "shortcut" of what's above, conclusion and my pick of the day is below. All three DAP-s do sound excellent, I have no doubt about it... of course price, build and UI quality aside. MA9 offers very musical and addictive sound, there's ton of smoothness there, and cherry on top would be excellent soundstage and imaging, those are the strongest points of that device in my book. It has the lightest, roundest and the most polite (still, with right IEM-s punchy as well) bass, but even though it's very, very good. MA9 highs may seem rolled-off but once you get used to them, they do sound very enjoyable. And overall presentation of this DAP some of you will consider as dead neutral, and another - a bit dark. If that kind of sound is your cup of tea, drink and enjoy, you'll thank me later. AK120 sounds very natural as well, though brighter than MA9. In comparison this device has a bit less rounded, yet punchier bass and very impressive soundstage, the biggest one out there, I'm utterly and constantly impressed by it. In terms of sound quality AK120 is a kind of safe choice, that's the way I see this DAP. HM-901 is one dynamical beast, the amount of energy this thing puts into music is beyond any other portable device I've heard thus far. But Fang's most expensive portable product isn't all about brute force. Yes, that's one of key features, but it also sounds very, very musical, its the brightest sounding device of all three, but not too bright, don't get me wrong. Thanks to that kind of presentation the amount of details HM-901 provides is very generous and this rocks my boat. And bass, I have to write it again, the best and lowest one I've heard thus far in DAP, for some time now it's a reference grade for me. And the soundstage, even though a bit more closer than the one competitors deliver, is also impressive. That's it. Let's get down to conclusion.
 
Final words
 
The time has come to sum things up. I may repeat myself couple times now, but I'm sure those of you who read only endings will be delighted. To be honest, there's no perfect DAP, even when it comes down to spending 1000$ or more, it's a kind of obvious thing to write. Yes, unfortunately we have to go to compromises and not much can be done about it. To some degree we can rely on firmware upgrades but that's about it. When choosing between MA9, HM-901 or AK120 we have to prioritize our needs. Those of you who have read what I wrote above will know what I'm about to do here. In terms of pure OS, MA9 is a way to go, this device has RockBox. AK120 with somewhat lagging, but fairly usable interface comes as a second, and in the end there's HM-901, which in that regard is slow and very limited in terms of available options. Physical buttons/touchscreen wise, MA9 is OK, AK120 isn't as responsive as I'd like it to be, but still usable, HM-901 is on the last place. In case of this particular DAP there's plenty of room for improvements, both in terms of build quality and OS, I'm sure HM-901 owners can confirm.
AK120 does the outdoor usability job way better than competitors, obviously due to its smaller size. HM-901, even despite being huge thing to carry aroud is still more usable on hand than brick alike MA9. If I had to choose one DAP mainly based on stuff mentioned above without SQ factor, I'd go with AK120, MA9 as my backup plan (RockBox FTW), HM-901 would be considered as a third option. But I'm sticking to the last one all the time, even despite of its UI/build quality issues I shared in this review. Yes, it's all about sound of HM-901. I can't help it, Fang did it oh so right.
In terms of pure sound quality, the way I see AK120 is that it's a great DAP and a safe choice to make. People who got AK120 are mostly happy, no doubt here, no matter if we're talking about casual users or audio junkies. Some of them won't even look back, beeing in seventh heaven thanks to sound quality that small DAP provides. But not me, I see AK120 as jack of all trades and master of none, with one exception: enormously big soundstage. Sure, it could only be me, as I got used a bit too much to my HD 800 and LCD-2, as those are on the opposite sides of the spectrum, very different sound signatures they provide. Hence maybe I'm all about opposites and nothing in the middle can break this wall, I'll leave you guys to decide whether because of that my judgment calls are biased. But to my ears HM-901 sits on one pole, MA9 has its comfy igloo on another and AK120 is placed somewhere in between those two. Again, to my ears it's not even about tonal balance, but the fact that HM-901 and MA9 simply give me more listening pleasure than AK120, on many levels. But lots of people are all about the middle, Astell&Kern flagship model will be their choice number one and I see nothing wrong with that as well.
As for sound quality of MA9 it goes like this: when I'm in right mood, sitting in the right chair, drinking right beer, contemplating about meaning of life in the right way and unexpecting spanish inquisition, well, I can literally drown and melt in that laid back sound, it gives me oh so much joy. Even with thicker sounding IEM-s, even despite those shouldn't get along with MA9. Yet they do, at least for me and it seems that when that happens - time stops, there's only me, music and this defense capable, aluminum brick sitting in my hand. Got carried away, sorry. But as I wrote, listening to MA9 is a kind of ceremony for me, right time and place are needed, nothing casual about it, no matter how funny or poetic this may sound. That's why this DAP is so special to me. And there's HM-901. Again, another metaphor is needed, but not so poetic this time. This device is like a vintage car to me. It may look arguably and have no luxury onboard, to a degree that even windows are handled by rusty, old and creaking winches. But who cares, this thing has 1000+ ponies under the hood. Therefore it's dynamic and fast as hell, I'm talking about a beast here, not a car. Aye, it can easily make me crash on the very first turn. But if I'm up for it, well, competition will be left far behind. And that's what HM-901 is all about, I'm all in, I can handle and appreciate it in 100%, I have proper tools and set of skills. When paired with my Heir Audio 8.A and hybrid IEM cable from Forza AudioWorks, well, it delivers the best sound on the go I've ever heard, period. That's why I'm constantly using HM-901, even despite its flaws and the fact that I really am spoiled by devices way more comfortable in use. Awkward, yes? But in this case sound quality is above anything else, I'm amazed, HiFiMAN flagship DAP is end-game device for me. At least until something better sounding shows up. Besides, it's hard not to like vintage cars, ain't it?
 

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P.S. If anyone is interested, below there are some product photos I did. They were published somewhere else, but I'm the owner of those.

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