Astell & Kern AK240 - Reviews
Pros: UI, storage capacity, streaming capability, native DSD playback
Cons: Expensive, runs warm after some time, battery life
When I first got this player through the mail I was amazed at the amount of power this device holds. Works great as a DAP or as a DAC with my mac since I have more of my music on there. The large storage was a huge plus for me since I have a large library. One of my favorite features though is that these players recently got the capability to stream Tidal from the device. With my Shure se846 I was further impressed when I paired it up with the player because the bass was significantly improved and when I play DSOTM in DSD I can really hear the difference from when I used to play it in FLAC. Overall, I think this player is one great device the battery life isn't as great as I'd like it to be when I play in higher resolution formats and after some time I have to stop listening when I feel the player is getting a bit warm. This player goes everywhere with me and I would highly recommend if you're willing to spend the money for the quality you're going to be getting with this DAP.
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What i did w/ my multi channel DSOTM was q.convert to FLAC, for the Battery's sake. i still keep the DSD files, Play them @ home esp. when i need to drain the batt. before sleeping. i always drain it up to @ 3 - 4 % remaining, then charging whilst device turned OFF
Pros: Almost everything you want in a player. Fabulous design, great sound, good UI.
Cons: Expensive.
I purchased this player to upgrade my Fiio X3 and the Colorfly C4. Both good players in their own rights, but out-shined greatly by the AK240. As one of the most powerful player at the time of purchase (2015) and maybe today (2017), the AK240 packs punch, quality and great UI into a relatively small package--at a price. 
Of course, Iriver products are known to be quite costly, but the 2,500 price tag will probably shy off most listeners. Is it worth it? I would say so. The sound quality and UI are both fabulous, and the battery life will last you for the day unless your earphones are glued to your ears. 
At the time of this review, however, AK have already launched their new flagship--the AK380, which comes at an even heftier price tag. For now, the "budget" AK240 still holds its own as one of the best players in the market. 
Bottom Line
The AK240 is a luxury product and doesn't disguise as otherwise. Then again, all Audiophile products are somewhat luxury products. If you love audio and price is (somewhat) an object, then go for the AK240. If you have really deep pockets, the AK380 is just waiting for you in some Amazon warehouse.
Pros: SQ, Excellent UI, Form factor
Cons: Battery life, price

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Pros: The sound quality is outstanding, both as a DAC and amp. The UI is polished and the unit itself is incredibly well built.
Cons: Not only is it phenomenally expensive, but requires the best IEMs or headphones and music to get the most out of it.

Thanks to slwiser, Spidermeng and Woody469 for some of the pictures used in this video.
Excellent review, very informative, thank you.  The features and performance appear to be justified the cost.  Just got my UERMs, so a nice DAP would be the next upgrade.    
How is the sound quality of this compared to a centrance- M8LX, and Chord Hugo
anyone use an AK240 with IE800's? Given I plan on buying HD800 the AK240 seems good for me. 
Pros: Unbelievable sound coming from a self-contained unit that is starting to intrude into the multi-component space in the portable audio world
Cons: Price, battery life, proprietary balanced connector standard


Before getting into the AK240, I'll need to thank Amos/Currawong for bringing this back from the SoCal 2014 show, and also a very big thanks to iRiver USA for being so generous on letting Team Tokyo have a loaner of this product. Where we can test in the comfort of our environment rather than standing in a shop with limited time for testing.
Is one needed for this DAP really? It's gained more attention before it was released than when it's available!! This is iRiver/A&K's latest addition to their line but it's also their flagship. The AK240 specs can be found below so there's no necessity to regurgitate in this review :-



Below was the AK240 launch in Japan. It shows how the design of the AK240 was conceived. Sadly I don't understand enough Japanese to understand what was said in the presentation, nor do I understand enough about design concepts.
When the AK240 was first released I thought the design looked awkward and many others thought so too. However having one in my hands right now, with it sitting side-by-side with some of the other competitor DAPs, there's something attractive and appealing about it's very space-age design looks. Even walking around in the streets and having a cup of coffee, passer bys do take a glance at it wondering what this James Bond-looking gadget is. It's not that I'm ashamed of looking geeky with my multi-stack DAC/Amp hanging off my iPad but it's also nice to have something that's modern looking that actually looks trendy to the non-audiophiles but yet produce audiophile level sound quality.
The positive side-effect of this is that then the general audio listeners will also start to take an interest in good SQ as the products not only appeal their sonic palates but to match their image lifestyles too. If there's any opportunity to raise awareness to the general public of how good music could sound to their ears, I'd be happy to support such an opportunity - even if it means designing something visually striking and easy to use around a audio component that delivers great sound quality.

Ergonomically though how well does it fit in one's hands? At least in mine, averaged size palm, it actually fits in quite well. When I first saw the AK240 on the forums, I wondered why have the smaller screen with the bigger base? One may as well make it a rectangular box design and put in a larger LCD. However when I have this in the palm of my hand (and I'm left handed), I can actually wrap my fingers and rest on the slanted bevel below the volume knob which provides me a more secure yet comfortable grip, which is a nice feeling to have when holding a $2500 item.
The AK240 also feels solidly built and robust - I feel that it's something classy in my hands. The volume dials are light with distinctive clicks signifying a 0.5 jump increments (of 0 -> 75). The power, back, pause/play, forward buttons are also distinctive and don't feel loose. The 3.5mm jack holds in quite firmly but not excessively. 
Aside from the external design and ergonomics, I thought I'd put in another picture from the Japanese slide presentation I attended. This has is a little more about the internal architecture of the DAP and how it uses the 2xCS4398 DACs for each channel :-


The AK240 is loaded with features which has made it a rather versatile DAP. It supports optical out, balanced out, functions as a DAC/Amp from a PC (not from Android), has WiFi for wireless upgrades, and online streaming, Bluetooth 4.0 support, and if 256GB internal storage is not enough, a microSD card slot with up to (the current) 128GB microSD can be further added.
I won't dwell too much on the WiFi MQS Streaming (hires) nor native DSD support as that's been discussed in the forums (although I will comment on it's SQ later) but I'd like to drop in a word or two about another service which hasn't been talked about much, mainly because the service is currently quite limited. The AK240 also supports online purchasing and downloading of hires quality music via the same MQS Streaming but through the Internet with some online music stores iRiver/A&K have partnerships with. Currently this service is available in Korea and (as I've been told) Germany. It's my understanding iRiver Japan is trying to provide this service in Japan too and since they had eOnkyo talk in their AK240 press release, I can only hope that iRiver Japan has a successful negotiation with them to provide hires and DSD downloading to the AK240 too.
Another feature which seems to be in the works is using the AK240 as a DSD DAC from the PC. Currently on firmware 1.09, it hasn't been very stable for me (the Audirvana Plus on the Mac side resets if I change volume on the software player, but it seems to work if I just let it play through without trying to change anything) but hopefully future firmwares will fix this and all the format supported on the DAP will also be supported as a DAC/Amp.


Sound Quality

When iRiver/A&K released the AK100, AK120, and AK100Mk2, they were (to me at least) revolutionary that they could make an audiophile level sound in a neat package that's aesthetically trendy and easy to use. But the SQ was still a little hit 'n miss that made me feel the makers were still experimenting a little (admittedly less so with the AK120 which was quite a solid product on its own). But the fact that they could be modified and improved internally meant to me that that the makers still hadn't nailed it. As such with the AK240, I think the makers has finally come up with something where (if we forget about the price), is something that sonically is it.
Personally I was skeptical myself of how "good" could a self-contained unit that fits in the palm of my hand could be, and my experiences with competing DAPs in the past had been minor incremental sonic improvements over each other that the reign of a DAP usually isn't very long lasting. The AK240, however was a jaw dropping easily noticeable marked improvement over it's predecessors. Not only that, but also given stiff competition to its peers.
The main primary sonic features I've noticed with the AK240 is how smooth and fluid it's musical presentation is. As I listen to quite a bit of older 50's & 60's west coast jazz, some vocal jazz with mainly few supporting acoustic instruments, the AK240 renders each instrument with precision, clarity and detail. Vocals are also very clear, involving, and smooth. However despite the precise distinction of each of these components, the AK240 pulls them all together that they all work in harmony together that it feels like I am listening to one single musical piece. Should I choose to focus on a particular instrument, I can hear it with ease with copious amount of detail but should I sit down and relax I can take it all in without any odd component standing out over the others.
I think this is helped by the large spacious setting the AK240 is able to create. The soundstage is wide as the imaging is deep. Placement of instruments and vocals on the stage are easily identified. But again, each component uses that space well. There are no pockets of 'vacuum' where the presentation sounds odd.
I find the AK240 to really start trickling into the multi stack portable DAC/Amp component space. Except for maybe the HM-901, I find comparing the AK240 to other DAPs to be an easy challenge and it has been more intriguing to compare it with the separate portable DAC/Amp products instead. Although there are some high end portable DAC/Amps that still have an edge over the AK240, the AK240 still puts up a good fight.
[Added: 7th Apr '14] The AK240 is not forgiving to poor recordings. In some older recordings and mastering, I can hear more background noise and imperfections during the recordings. Any skepticism I had with the CS4398 as a DAC from my older Marantz DV9500 SACD player are changing and I understand more that it's the implementation around the DAC that is just as relevant as the components used.

AK240 & NW-ZX1

Sadly my favourite NW-ZX1 was easily toppled by the AK240. Again we should, for the moment, forget about the price of the products. The AK240 to my ears sound smoother, greater depth, and that fluid presentation makes my NW-ZX1 sound somewhat less refined by comparison. That's not to say the NW-ZX1 is a terrible product, as I opted it over the AK120 which I subsequently sold. However the AK240 is a noticeable step up over both the NW-ZX1 & AK120.
Why would I choose the AK240: Greater storage, better SQ, greater flexibility with balanced output
Why would I choose the NW-ZX1: Great value for money, UI more dummy proof, open Android platform. Won't cry so much if I lose this since it's cheaper than the AK240.

AK240 & HM-901

This is one where it does get a little more interesting. The AK240 sounds more coherent than the HM-901 where I find the HM-901's separation to be a little too distinctively separate left & right (especially vocals). The HM-901 does have a deeper and greater sub-bass impact, with a mid-bass bloom. As such the HM-901 does sound somewhat more warm and mature, whilst the AK240 seems to focus more on the upper mids to treble space. I do find the trebles in the AK240 a little more compressed compared to the HM-901, but not offensively so. Overall FR though, the AK240 comes back though by having a greater sense of space in width and depth whilst the HM-901 sounds more intimate by comparison. When I have these two DAPs side-by-side, the HM-901 feels like the more older mature CEO of a large business, whilst the AK240 more the slick & smooth yet precise banker.
Why would I choose the AK240: Faster and more logical UI, more standard charging interfaces with its microUSB, longer battery life (just), good for HipHop, R&B
Why would I choose the HM-901: Cheaper than the AK240, more mature sound for the slow easy going, Jazz, vocals, golden oldies, 80's pop 'n rock. Can drive those harder-to-drive cans, modular amp options. A more standard(??) 3.5mm TRRS socket for balanced headphones.

AK240 & the CLAS -dB/Duet

The AK240 comes close to the Cypherlabs component stack and puts up a good fight against it. The -dB/Duet is able to match the staging width and imaging depth but also has the bass depth similar to the HM-901 in comparison to the AK240. The Duet is also has a more powerful amp section than the AK240.
Why would I choose the AK240: Compact, greater storage than any iOS or Android device with the -dB/Duet stack
Why would I choose the -dB/Duet: I'll sitting in some cafe for an extended period of time with my obnoxious large cans. It'll charge my iPhone whilst I'm listening to it. A more common socket with the Kobiconn for balanced headphones.

AK240 & the VentureCraft DD OPA627SM 12V LE/Apex Glacier

The AK240 still provides easier instrument separation and a mid-row from stage presentation, whilst the VentureCraft DD/Apex Glacier has a more front row stage presentation. (Typical of OPA627's??) There's more bass warmth to the VentureCraft DD/Apex Glacier but this stack also seems to have smeared details when compared side-by-side to the AK240.
Why would I choose the AK240: Compact, greater storage than any iOS device with the DD/Apex Glacier stack (note the DD is an iOS-only device), sonically more detailed and precise. I have a balanced headphone option if I want.
Why would I choose the DD/Apex Glacier: cheaper than the AK240, more configurable that I could switch amps.


As I mentioned earlier, before this product was in my hands and all I saw were pictures, I was a skeptic. Whilst I thought that it'll be a good product, I didn't think it'll be a great product. The price will deter most from even trying the AK240, and maybe the design may too. However if one were to put those pre-conceptions aside, and just get to touch, feel and hear the AK240, hopefully they'll see its inner beauty. Whether that is worth the asking price, that is up to each individual.
For me at least. I believe in bridging the gap between the image of geeky audiophiles with their geeky looking products with the more mainstream audio enthusiasts and where in the past these audio enthusiasts get turned off by audio products that may sound good but look horribly designed, products like the AK-series show that one could get good sound yet still not look awkward. Whilst it's true that the price of the AK240 may still make it prohibitive to the general consumer, it's closer within the reach of some of the audio enthusiasts and enlighten them a little more on what audiophiles are raving about - without looking too awkward.
Where the AK240 excels, I feel, is that as a complete self-contained package - sonics, capacity, usage, functionality, visual and feel aesthetics - the AK240 is a winner. It sits in one's pocket unobtrusively, it's basic functions are easily accessible with external buttons, it can function as a DAC/Amp with a notebook, it supports balanced headphones out, it supports line out, it has copious amount of storage, it can stream high quality music wirelessly, it even supports online download in countries where the service is available, and it doesn't sacrifice quality in doing all these things.
For me, my AKR03 sounded similar using both outs when I first got them. But after a week of burning in, they started to sound quite differently between the 2 outs, there seems to be a lot more bass boost with the SE out, but quite balanced sounding with the balanced out. Maybe be I should get my other IEMs' cables re-terminated to balanced too to see what it'll be like.
No specifications ?
@zorin, nope. Sorry. This is more an impressions rather than an introduction of a product.
Pros: Outstanding sound quality, the best UI of any audiophile DAP thus far, unparalled build quality, innovative Wi-Fi features (streaming, etc.).
Cons: Should include balanced adapter, runs warm, price point can be a significant barrier to entry for some.
REVIEW: Astell & Kern AK240
Tuesday, February 25th, 2014
by Warren Chi & Michael Liang

Editor's Note: If you haven't read (or don't remember) our Astell & Kern AK120 Roundtable Discussion from last year, please take a moment to review it now. We came to some conclusions in that discussion, conclusions that shaped our views moving into this review.

When it comes to Astell & Kern, we have a running joke here at Audio360... if you get one of their players, you're gonna get screwed.
But before you get the wrong idea, you should know that this actually has very little to do with Astell & Kern, and everything to do with our friend and fellow 360er, Michael Mercer. You see, Mercer has this wicked habit of laying down a substantial grip of cash on a new Astell & Kern player – right before they release a newer (and better) model.
This is what happened with the AK100. Shortly after he decided to buy his evaluation unit, Astell & Kern released the AK120. We gave him a bit of a hard time about that, as we cruised around with our own AK120s. And of course, we never missed an opportunity to let him know – in no uncertain terms – what a great time we were having. Because of this, he finally broke down and requested an AK120 evaluation unit to see what all the fuss was about.
It didn't take him long to realize it was a significantly better player. And soon after we published our Astell & Kern AK120 Roundtable Discussion, he decided to purchase his AK120 evaluation unit as well. We were happy for him... for all of three weeks... because that's when we learned about the new Astell & Kern AK240.
One month later, the AK240 made it's debut at CES 2014. Mercer was among the first of us to check it out, and he wasn't exactly happy about it. See that grin on his face? Despite what it looks like, we can tell you that is not the expression of joy that you think it is. And if history repeats itself, we're headed for some trouble here.
You see, although his sense of timing is a riot for us, it wasn't that funny for him when it happened with the AK100 - a $699 player. It'll be even less amusing if it happens with an AK120 – a $1,299 player. This is why we decided to spare him some angst and keep him out of this review. If he found out that the AK240 is even half as good as he thinks it might be, he'd burst a vessel.
After spending quite a bit of time with the AK240 recently, and having discovered what a magnificent piece of kit it is, we know with every fiber of our beings that we did the right thing in keeping it from him. Mercer, bro, you don't even know... but we just totally saved your life!
  1. Supported Audio Formats: WAV, FLAC, WMA, MP3, OGG, APE (Normal, High, Fast), AAC, ALAC, AIFF, DFF and DSF
  2. Sample Rates: FLAC/WAV/ALAC/AIFF = 8 kHz~192 kHz (8/16/24 bits per sample); DSD64 = 1-bit, 2.8 MHz, stereo; DSD128 = 1-bit, 5.6 MHz, stereo
  3. Output Level: Unbalanced = 2.1Vrms; Balanced = 2.3Vrms (Condition No Load)
  4. DAC: Cirrus Logic CS4398 x2 (Dual DAC)
  5. Decoding: Support up to 24bit/192kHz Bit to Bit Decoding, DSD64/DSD128
  6. Input: USB Micro-B input (for charging & data transfer via PC & MAC)
  7. Connection Mode: MTP (Media Device)
  8. Outputs: PHONES (3.5mm) / Optical Out (3.5mm) / Balanced Out (2.5mm, only 4-pole supported)
  9. Wi-Fi: 802.11 b/g/n (2.4GHz)
  10. Bluetooth: v4.0
  11. Dimensions: 2.59 "(66 mm) [W] x 4.21 "(107 mm) [H] x 0.68 "(17.5 mm) [D]
  12. Weight: 6.5 oz (185 g)
  13. Frequency Response: ±0.023dB (Condition: 20Hz~20kHz) Unbalance & Balance / ±0.3dB (Condition: 10Hz~70kHz) Unbalance & Balance
  14. Signal to Noise Ratio: 116dB @ 1kHz, Unbalance / 117dB @ 1kHz, Balance
  15. Crosstalk: 130dB @ 1kHz, Unbalance / 135dB @ 1kHz, Balance
  16. THD+N: 0.0007% @ 1kHz, Unbalance / 0.0005% @ 1kHz, Balance
  17. IMD SMPTE: 0.0004% 800Hz 10kHz(4:1) Unbalance / 0.0003% 800Hz 10kHz(4:1) Balance
  18. Output Impedance: Balanced out 2.5mm (1ohm) / PHONES 3.5mm (2ohm)
  19. Clock Jitter: 50ps (Typ)
  20. Battery Capacity: 3,250mAh 3.7V Li-Polymer Battery
  21. Built-in Memory: 256GB [NAND]
  22. External Memory: microSD (Max 128GB) x1
  23. Display: 3.31inch WVGA (480 x 800) AMOLED Touchscreen
  24. Feature Enhancements: Firmware upgrades supported (OTA)
  25. Body Material: Aircraft Grade Duralumin
  26. Body Color: Gun Metal
  27. Supported OS: Windows XP, Windows 7,8 (32/64bit), MAC OS X 10.7 and up
Design & Appearance
One of the most polarizing aspects of the AK240 is its design: some love it, others hate it. We're not surprised - its appearance is a far departure from anything we've seen by Astell & Kern, or any other portable music player on the market for that matter.
We'll readily admit, when we first laid eyes on the AK240, we weren't wild about its design. This was due - in part - to some unflattering pre-release photos that didn't accurately convey scale or proportion, emphasizing forced perspective, and obscuring the planform alignment that is a hallmark of the AK240's design.
Since then, we've come to deeply appreciate the AK240's faceted design.
Regardless of how you may feel about the design from a purely visual standpoint, there are a few things worth noting about its form factor:
  • In our experience, the AK240's design is a case of love at first grasp. While it may seem clunky and unwieldy in photographs, the genuine article is anything but. As soon as we held it and started using it, we were both astonished and puzzled at how ergonomic it was, especially for something so angular.
  • Depending on which hand you hold it with, the starboard ledge serves as either a thumb rest or finger rest, leading to less grip fatigue. In addition, the irregular facets on the starboard ledge also do a good job at leaving the volume knob accessible to user rotation, while protecting it from accidental OMGWTFSOLOUD!
But if you're still bothered by the AK240's aesthetics, you should know that they are largely insignificant.
We don't mean to sound apathetic about its form, and we certainly don't mean to offend the industrial designer behind the AK240, but we just didn't spend any appreciable amount of time actually looking at the thing. During its stay with us, the AK240 resided primarily in our pockets, messenger bags, and hands (where we tended to focus on the screen and not the casing).
So if you've been eying the the AK240, but aren't too thrilled about its styling, just know that it's all about mind over matter: (a) you won't see the design very often; (b) when it's out of sight, it's out of mind; and (c) if you don't mind, then it don't matter.
Build Quality
The Astell & Kern AK240 is exceptionally well-built using premium materials, as befitting a top-of-the-line luxury product.
Actually, that's a bit of an understatement. Each AK240 is meticulously constructed to exacting standards from portmanteaus (e.g. Duralumin) and carbon fiber - through a process employing diamonds and lasers.
This results in a unit that is impeccably solid in-the-hand. Matter of fact, we can't remember the last time we came across a handheld electronic device that is so unyielding, so adamantine in structure. And in case you're wondering how this affects durability, we can tell you that it is absolutely essential.
We're happy to confirm that the AK240 is built-to-last. It stands up well to both daily use as well as the klutz factor - as solid as it is in-the-hand, it's even more resilent when it falls out-of-hand. We learned this very early on, shortly after picking up our evaluation unit: the first drop (and accompanying "oops") came just minutes after having been cautioned about how few and rare AK240 evaluation units were. Shhh, don't tell Astell & Kern.
While we didn't keep track of how many subsequent (and inadvertent) drop tests were "performed" - well let's just say that we are pleasantly surprised at how the AK240 managed to remain immaculate and pristine. There are no dents, scratches or marks to be found anywhere, including the screen. And of course, the electronics remain in perfect working order.
So solid is the AK240, that we'd want it at our sides should an audiophile gang war ever erupt. If we ever had to throw down, having AK240s in our fists would be devastating. What? It could happen... after all, we already have our own gang sign.
Features & Functionality
Astell & Kern announced the AK240 with a bevy of new features intended to satisfy discriminating personal audiophiles:
  1. MQS Streaming via Wi-Fi
  2. OTA Updating over Wi-Fi
  3. Native DSD playback
  4. Finer-Resolution EQ
  5. Balanced Output
MQS Streaming via Wi-Fi
One of the AK240's most exciting new features is the ability to stream music - wirelessly - from any PC or Mac that's connected to the same network as your AK240. This gives you easy access to a virtually unlimited amount of music: as much music as your PC/Mac can hold within its internal and external drives.
To make this work, you'll need to install Astell & Kern's MQS Streaming Server software on every PC/Mac that you want to share music from. It's nothing terribly demanding or CPU intensive, just a basic media server coded to shake hands with an AK240 (and presumably future Astell & Kern DAPs as well).
For more information about Astell & Kern's MQS Streaming Server software, visit:
Once installed, simply add the folders that your music is stored in, and your PC/Mac is now configured to share music. Back on the AK240, you'll want to connect to the same network that your PC/Mac is on (via Wi-Fi) and select "MQS Streaming" mode on your AK240. It will automatically see all of your music shares. That's it!
Warren (PC): This was super-easy to setup, and even easier to use. Within minutes, I was up and running, using the AK240 to stream any song I wanted from my PC. Plus, I could also download (i.e. copy) a song from my PC over to the AK240 by giving that track a couple of screen taps. Just be forewarned: it can sometimes take a while to retrieve all of your songs, particularly if you have a lot of them jammed into one huge folder, so try not to organize your music that way.
Michael (Mac): It didn't work for me. :frowning2: I'll look into this more and give everyone an update when we cover balanced output.
Of course, this feature does leave one thing to be desired... because it requires the MQS Streaming Server software in order to work, you won't be able to pull music directly from your NAS drives. As a workaround, we presume - though we have not verified - that you could probably just map your NAS drives on a computer that does have the MQS Streaming Server installed, and stream them from there. Still, it'd be nice to avoid turning on a computer at all. Astell & Kern agrees, and they are now looking into the possibility of streaming music directly from NAS drives.
We hope they find a way to add that feature soon, and present it as a gift in the form of a free update. Speaking of updates...
OTA Updating over Wi-Fi
Major new features like MQS Streaming are all well and good. But sometimes, it's the little things that make us all wet. Enter the AK240's "OTA Updating over Wi-Fi" feature - which is really just a fancy way of saying wireless firmware updates.
Seriously though, wireless firmware updates? How cool is that?! No more patch downloads, tenuous USB connections, or bated breaths. Now we get a shiny new system in return for a few taps. That's a fair exchange, we can live with that.
To test this out, we performed a firmware update as soon as the AK240 alerted us (via the notifications tab) that there was such an update. You can also perform an update manually by going into the Settings > Update > System Update if you want. Either way, the process is a no-brainer:

  • You'll get a dialog box that there's new software available, and be asked if you want to perform an update.
  • Click "OK" and the AK240 will begin downloading the new firmware. For us, this was a 118MB file that only took a couple of minutes. By the way, once the download is done, you won't need a Wi-Fi connection anymore. So if you're in a rush to leave the house, go right ahead.
  • The AK240 will then confirm that you want to update, and warn you that it will reboot. Click "OK" and it will reboot - immediately.
  • At this point, the AK240 no longer needs you. It will take itself through a series of alternating progress bars and reboots until it's done - at which point it will deposit you back at the home screen. That's it.
Our firmware update took us from version 1.05 to version 1.07. Other than making the AK240 quicker overall, we have no idea what it actually updated. Does it matter? There was an update, so we updated, and you will too. Now that the hassle and chore of performing updates has been eliminated, it doesn't really require a second thought. Again, very cool... very this millennium.
Okay fine, sliced bread it is not. But on the other hand, if it's not a that big a deal, then why don't other audiophile DAPs do it?
Native DSD playback
Fourteen years after Sony released the first SACD player (SCD-1), we are now at a point where we are starting to see DSD downloads getting some traction.
But getting those files to play requires some jumping of the through-hoops variety. On the computer, a third-party application like Korg's Audiogate or PureMusic is required to play the files. You'll also need a DAC that can process 1-bit DSD. Even with those two things, the playback isn't exactly enjoyable.
If you plan to make the move to DSD, the AK240 is your new BFF. Unlike the AK100/AK120, the AK240 now supports native DSD playback, without converting it to PCM first. And while the AK240 is not the first DAC/amp to support DSD natively, it is the first and only audiophile DAP to do so - at least until the Calyx M is released.
The AK240 will handle both DFF and DSF files in either 1-bit 2.8 MHz single-DSD or 1-bit 5.6 MHz double-DSD. No other hardware is required. Select your favorite album and hit play. The AK240 handles everything internally.
Now that's a winning recipe to DSD playback.
Our evaluation unit came preloaded with some sample music in DSD, so we decided to give it a listen. Sure, it sounds impressive... most impressive. But the supplied music didn't exactly float our boat, so we moved on.
Finer-Resolution EQ
We don't use equalization. But those who do will be happy to know that Astell & Kern has increased the number of gradations in their graphical EQ, allowing for a finer and more granular control in sound shaping.
Where the AK100 and AK120 each offered a 5-band user EQ, the AK240 offers a 10-band user EQ, with each of those bands being adjustable in 0.5 dB increments through a range of ±5 dBs. And finally, it is now possible to create and save multiple EQ curves to better suit changing moods, genres, etc.
Balanced Output
Since the AK240 was intended for home use as well as portable use, Astell & Kern began thinking out-of-the-box when they designed the AK240. What would people want as part of a home listening rig? What would need to be included in a portable DAP, that isn't typically found in a portable DAP?
The answer they came up with was balanced output. It's not nearly as crazy as it sounds. There is a multitude of headphone amps - both desktop and portable - that features balanced outputs.
There's just one minor hitch. The AK240 uses a non-standard 2.5mm TRRS jack for balanced output. And, as you would imagine, we have exactly the same number of 2.5-TRRS-to-XLR adapters as you do: none, zero, nada, zilch, Ø. So while we'd love to give you some detailed impressions of how the AK240 sounds in balanced operation, that ain't gonna happen today.
That said, we did have a chance to hear an HD 800 in balanced mode (via an adaptor) the last time we visited with Astell & Kern. It was a brief listen, but it was bloody fantastic.
We'll bring you an update in the weeks ahead, as soon as we source some adapters. They'll probably come from Moon Audio. Drew Baird over at Moon has the uncanny ability to make just about any kind of interconnect one could ever want. We'd be surprised if he hasn't already received a few requests for these adapters.
In our Astell & Kern AK120 Roundtable Discussion last year, we came to a consensus that the AK120 was the best sounding DAP we had ever heard. We also came to the conclusion that it left something to be desired in terms of usability, even if it was far easier-to-use than any competing audiophile DAP at the time.
With the AK240, that caveat about usability no longer exists. Taking AK100 and AK120 user feedback to heart, Astell & Kern went back to the drawing board and developed an Android-based custom UI that isn't just good for an audiophile DAP, it's just good period. Actually, it's better than good. The AK240's user interface is superb and nearly flawless.
If you haven't already seen it, check out Jude Mansilla's AK240 UI video on Head-Fi TV to get an idea of what we're on about.
We found the AK240 incredibly responsive and lively, reacting to every gesture with the kind of immediacy and alacrity one would expect from an iDevice (or high-end Android device). Taps were easily registered, and scrolling was consistent, without stalls or jitters.
Feedback animations were silky smooth, with no perceptible stutter to speak of, and take no more than a fraction of a second to complete. The one exception to this was the notifications pulldown, which was blazingly fast and nearly instant, exactly as it should be.
In fact, the only semblance of a lag came when the AK240 was scanning for new media, during which we had to wait a few milliseconds more for the obedience that we so richly deserve.
Navigating through the music library was both intuitive and effortless, much like it was with the AK100 and AK120. From the home screen, one can browse through the library by songs, albums, artists, genres and folders, as well as access playlists, all via a logical drill-down schema.
In addition, Astell & Kern spent a great deal of time and effort in streamlining the number of gestures required to perform tasks. As a result, commonly accessed actions and settings are always close at hand. For example, when playing a song, the following actions can be performed fairly quickly:
  1. Accessing song lyrics: one tap
  2. Accessing song metadata: two taps
  3. Enabling or disabling EQ/gapless/Wi-Fi/Bluetooth: a swipe and a tap
  4. Changing repeat and shuffle modes: also a swipe and a tap
  5. Adjusting screen brightness: a swipe and a slide
  6. Adding a song to a playlist: two taps and a swipe
And thanks to a new dedicated, hardware-based home button, getting back to the home screen is only one tap away, no matter where you are or what you're doing.
New UI Features
In addition to the improvements above, the AK240 is also equipped with several new features that greatly enhance the user experience. Some of the following are part and parcel to Android itself, but we are still glad to see them put to good use.
Adaptive Scrolling with alphabetical indexes. Scrolling through long lists of songs, artists and albums just got easier. In addition to faster response times allowing for smoother scrolls, there is now an alphabetical index bar that appears on the right. It lets you quick-jump to blocks of song titles, artist names, and album names by selecting the first letter in that name.
Search function, with instant search results. Know exactly what you're looking for? You can now search directly for the exact song you want. To help you save even more time, search results appear instantly with each letter you type, broken down by artists, albums and songs, beginning with the very first letter in your query.
Android alphanumeric keyboard. Of course, in order to enter in search terms, you'll need to type in characters. For this, the AK240 includes the standard Android keyboard, which features alphanumeric characters as well as a decent selection of symbols. This keyboard is also used to name and rename playlists on-the-fly. What more could we want? Well actually, we wouldn't mind the ability to edit metadata directly in the player, but now we're just nitpicking.
Customized Android notification tab. Astell & Kern's implementation of Android's notification tab puts a wealth of options right at your fingertips. Simply swiping down the tab give you access to search, Wi-Fi, Bluetooth, file transfer methods, EQ, gapless playback, shuffle modes, repeat modes and brightness settings. And of course, it also alerts you to various system and network events.
As a matter of fact, a new notification just popped up letting us know that there is a firmware update is available: "New firmware file is exist at server." What you say!! Somebody set up us the firmware? Yippee!
While these features aren't particularly innovative or groundbreaking, they are tremendously helpful in the preservation of both time and sanity in daily usage.
But the single most important (and most readily noticeable) UI improvement is the AK240's new 3.31-inch AMOLED screen.
While we found the AK120's screen quite acceptable, having a full-sized touchscreen at our fingertips proved to be a lifesaver. With 82% more area, it just made everything that much easier.
The WVGA (480 x 800) display is crisp and sharp, with enough resolution to render microfonts smoothly and legibly. The colors are vivid but not overly saturated. And there are 12 brightness levels to work with - the brightest of which is easily viewable even in direct sunlight. It's simply brilliant, both literally and figuratively.
Less is More
And finally, we'd like to applaud Astell & Kern for something they didn't do: package in any bloatware. There are no apps, games or web browsers hogging up memory or chewing up CPU cycles. The AK240 is a high-fidelity music system - no more, no less. It's not trying to be a second phone or tablet, and we appreciate that.
All of the above work together synergistically to produce a user experience that gets out of the way, as any good user interface should.
Sound Quality
Avid personal audio enthusiasts know that hearing a wide variety of gear can breed apathy, making us jaded, blasé and hard-to-please. As such, it is indeed a rare occasion when a new piece of gear resonates with us immediately, right from the very first listen. Unfortunately for Astell & Kern, we went into this review having heard a lot of good gear lately.
Fortunately for Astell & Kern, their new AK240 sounds utterly and totally !@#%&$ amazeballs!
The AK240 features an unexpectedly neutral signature that is remarkably free of coloration. This stands in marked contrast to much of the gear we've auditioned lately - where certain portions of the spectrum are emphasized at the expense of others, as if to feign an intended signature in a thinly-veiled act of self-compromising defeatism. The AK240 makes no such excuses, it doesn't need to. Its rendering of frequencies is balanced, with few flaws advanced or merits withheld. It simply doesn't have an agenda.
This neutrality and balance helps ensure that the AK240 presents us with an accurate and faithful representation of the music we feed it - with the exception of lower bit rate compressed music, which the AK240 neither forgives nor abides. But with anything 16/44.1 or above, the AK240 is uncannily spot on - especially in tonality, where the AK240 renders piano accurately and consistently.
Despite having a flatter signature, which can often leave an impression of smoothness and refinement, detail retrieval is one of the AK240's strong suits. Its even-keeled signature is devoid of significant spikes or peaks that would exaggerate macro-detail. As such, there are very few macro-detail distractions that would - left unchecked - mask or drown-out micro-detail.
And finally, the AK240's soundstage and imaging is beyond reproach for a DAP. It is neither preternaturally expansive nor suffocatingly intimate. Instead, we are given all the air and dimensionality needed to present the music with multi-layered depth, as demonstrated by the AK240's deft handling of orchestral and symphonic music.
These are the sonic qualities that stood out for us in audition after audition, through a multitude of personal reference headphones and IEMs, with files ranging from lossy MP3 to 2.8 MHz DSD. Time and time again, we were rewarded with a level of fidelity that we honestly did not expect from a DAP.
Warren: Although the AK240 plays well with a wide variety of headphones and IEMs, I was repeatedly struck by the synergy of two extraordinary pairings: Audeze's LCD-XC and Ultimate Ears's UERM.
Piano Concerto No. 1 in E minor, Opus 11: II. Romanze - Larghetto (Conductor: Jun Markl / Soloist: Ingrid Fliter) from Chopin: Piano Concertos (FLAC, 24/96) via Audeze LCD-XC
I've not listened to very much classical piano in recent years, and had forgotten how sublime and moving Chopin can be until I stumbled upon this soul-stirring recording. I honestly don't know what it is about this rendition that I find enthralling, but there seems to be an uncommon sense of purity about it, with very little adulteration introduced through the performance, recording, mastering and playback processes to get in the way of my communion with Chopin. And though the AK240 and LCD-XC are at the very end of that long delivery chain, I feel immensely gratified that they did little to mar the experience.
"Embraceable You" from Too Much In Love To Care by Claire Martin (FLAC, 24/96) via Audeze LCD-XC
While Claire Martin's performance isn't my all-time-favorite rendition of this Gershwin standard - that honor belonging to Miss Paula West - I found this recording delightful nonetheless. This was especially true with the AK240 and LCD-XC at the helm, as the pairing married Martin's vocals and Kenny Barron's fingerboard work into a flawless collaboration of two stellar talents. The AK240 preserved all the detail necessary to flesh out a sparse Cabaret session, while the LCD-XC contributed enough low-end weight to give the piano accompaniment a touch of visceral presence.
"Everywhere" from The Very Best of Fleetwood Mac by Fleetwood Mac (AIFF, 16/44.1) via Audeze LCD-XC
Sure it's Eighties Top 40 Pop/Rock, but "Everywhere" has stood the test of time better than expected, and found new life in this remastered version from their latest hits compilation. Here, the AK240 and LCD-XC demonstrate exceptional imaging and dimensionality. Anchored by John McVie's bass taking stage left, and counterbalanced by Buckingham's easy-going guitar work from stage right, Fleetwood's drum work comes at you from an elevated rear stage before swirling around Christine McVie's center-stage vocals. Follow all this with Nicks's backing - which seems to fill all the voids in between - and you have a complete and lush soundscape.
"Get Your Hopes Up" from Lucky To Be Me by Taylor Eigsti (FLAC, 16/44.1) via Ultimate Ears Reference Monitor (UERM)
Eigsti leads an ensemble of talented players, including jazz guitarist Julian Lage and bassist James Genus, in this improvisational jaunt. In pairing the AK240 with the UERM, I was fortunate enough to maintain neutrality throughout the signal chain. And for this, I was rewarded with an accuracy in tonality that's hard to come by. The confidence of Eigsti's piano work stayed intact as he traversed the keyboard, instead of dissolving into a mess of indecisive timbres. Factor in the exquisitely natural sense of detail, and this track evolves into a splendid reference of what this pairing is capable of.
"Oraanu" from Cartographer by E.S. Posthumus (FLAC, 16/44.1) via Ultimate Ears Reference Monitor (UERM)
This E.S. Posthumus vocal anthem can be rather dense and incoherent when played back on lesser gear. But through the AK240 and UERM, Oraanu was as good as I've ever heard it, if not better. The AK240's staging and imaging abilities layered the ambient elements of this track beautifully. It left me with the impression of being that embryonic central doll at the heart of a set of Russian (nested) dolls constructed of entirely of sound, with ever larger dolls radiating details inward from ever increasing distances. And throughout all of this, the UERM's powers of coherency stripped some of the thick chorus effects from the lead vocals, bringing them into pristine focus, and keeping my attention from wandering too far. It was funky, but intoxicatingly euphonic.
Michael: Getting your own music on the AK240 is as easy as drag and drop. For Mac users, the free Android Files Transfer application is required. Thanks in part to internal flash memory, file transfer speed was relatively fast.
In no time I was transported back to 1993, in the audience of Uptown MTV Unplugged, Jodeci was on stage singing their version of Stevie Wonder's Lately. Although it wasn't high-res or "audiophile" music, with the sound I was getting through the Beyerdynamic T51p, it might as well me. K-Ci and Jo-Jo's powerful vocals came through with emotion thanks in part to the AK240 having just the right amount of decay. The piano in the back is clearly defined and when the bass notes came in, they did so with tightness with impact, never once overpowering the track.
Next album to sample was Anoushka Shankar & Norah Jones "Traces of You". This is a beautiful collaborative album by two half-sisters blending the sitar with the piano. The AK240 brought out all the subtle details with well-defined stereo separation, the track Metamorphosis sounded 3D. It's unbelievable that I'm listening to CD quality 16/44.1kHz.
But the real magic was pairing the AK240 to AKG's new flagship K812 headphones. This headphone is not for the average listener, it is HONEST, it does not sugarcoat low-quality sources or materials. You give it garbage and it will put you in a dumpster and take you to a landfill.I am pleased to tell you that the AK240's dual DACs and internal amplifier is up to snuff for the K812.
Giving the preloaded tunes some love, Rebecca Pigeon's Spanish Harlem in 24/176.4kHz through the K812 can be summed up in one word - glorious.
With regards to battery life, we were able to get 8~9 hours of play time from a single charge when we ran standard lossless (16/44.1) files. This dropped to approximately 5~6 hours of play time from a single charge when we ran high-res lossless (24/96) files.
We didn't play nearly enough DSD to get a sense of how long the battery would have lasted then, though we feel comfortable in making the assumption that it would not have lasted any longer than it did with high-res (24/96) files.
The only other audiophile DAP that even comes close to the Astell & Kern AK240 in terms of marrying performance, sound quality, design, build quality and usability is the Astell & Kern AK120, along with its steroidally-enhanced sibling, the AK120 Titan.
Unfortunately for Astell & Kern, the gulf between the AK120 and the AK240 is so wide as to render this comparison a landslide. As such, we offer an apology to Astell & Kern in advance. We generally prefer to compare units that are similar to each other, as opposed to having a successor beat up on a predecessor. But since they went ahead and created a new device without equal, toppling the crown from one of their very own, they've left us with little choice in the matter.
The Astell & Kern AK240 is superior by every perceivable measure.
Performance: the AK240 easily wins out by offering better file support (including native DSD playback), far more on-board storage and storage in total, and a more robust OS that runs faster and smoother than we expected: even library scans through vast amounts of music are handled quickly, as background tasks no less.
Sound Quality: While the AK120 doesn't sound bad, the AK240 trounces it, soundly. This was plainly evident from our very first A/B, and remained consistent through every subsequent A/B.
The AK240's signature is noticeably less-colored than that of the AK120. It's flatter, far closer to neutral, and more balanced than the AK120... with a more accurate sense of weight and mass throughout the midrange for tonality that is more true-to-life. As a result, the AK240 sounds smoother, cleaner, and more transparent overall.
By contrast, the AK120 leans a little warm due to its emphasized upper bass and lower mids. Pair this with a mild boost in the upper mids, and you wind up with a signature that is richer and fuller than that of the AK240. It's a presentation that most would classify as being musical and engaging compared to the AK240.
In terms of detail retrieval, the AK240's even-keeled signature offers us exceptional micro-detail, where the AK120 favors macro-detail that tends to mask such minutiae. Then there's staging, where the AK240 is discernibly more expansive and dimensional, able to render depth and dimensionality where the AK120 presented intimacy.
If we were to sum up the AK240's overall presentation in a single word, we'd have to say it's honest. In reducing the AK120's presentation to a single word, we'd say it's evocative.
Having said that, we'd like to reiterate that the AK120 isn't bad at all. It's particular flavor of coloration is actually quite pleasing. But if you're seeking a greater sense of fidelity, you'll prefer the AK240.
Design: The AK240 is an excellent example of form supporting function, as opposed to form existing on its own outside of function. Is the AK240 better looking than the AK120? No, we don't think so. But does its design help to make the AK240 an overall better product than the AK120? Yes, absolutely.
Build Quality: Owing to its unibody construction, the AK240's build quality is ridiculously solid, inspiring confidence whenever it's your hand. It's also virtually seamless, with gap tolerances that are far closer than the AK120, which already features world-class build quality in and of itself.
Usability: The AK240's usability is light years ahead of the AK120 in every possible way. Navigating through music collections is both clear and intuitive, in both native and streaming modes. Commonly-accessed tasks and settings are rarely more than a gesture or two away. And the AK240's responsiveness is easily the equal of any touchscreen device on the market.
That wasn't much of a contest was it? And once you factor in the AK240's exclusive features (i.e. streaming, balanced output, native DSD playback,etc.), the scales tip in favor of the AK240 even more. Simply put, there's no shame in getting the AK120, but get the AK240 if you can.
Astell & Kern's new AK240 is set to retail for $2,499.00 USD.
That makes it audiophilia's most expensive portable player - even more expensive than the stupefyingly-costly Tera player by a fair margin. However, unlike the Tera player, the AK240 is actually worth the investment... and here's why:
For many personal audio enthusiasts, the Astell & Kern AK240 - when paired with synergistic headphones or IEMs - is all they'll ever need to achieve audio bliss, both at home and on the go. It's a complete high-fidelity signal chain all unto itself.
With up to 384GB of storage, the AK240 is capable of holding an abundance of music for portable use. For home use, the AK240 offers users two options: it can be used as a traditional USB DAC; or it can serve as a wireless DAC/amp, streaming files from a virtually unlimited repository of music (from PCs and Macs on your network).
In all of the above cases, the AK240's dual-DAC implementation features the ability to decode any number of audio formats (including native DSD), making it a superb source (or a component thereof) for all of your high-fidelity digital music.
The AK240 also features an improved headphone amp over those of its predecessors and competitors, capable of driving a wide variety of low-to-medium impedance headphones. It's reasonably low output impedance also handles IEMs and CIEMs without much issue.
Of course, if you find yourself needing or wanting more voltage or headroom for your high-impedance headphones, you can elect to add a supplemental headphone amplifier. However, it's worth noting that the AK240's built-in amp is quite robust. It was able to drive a Sennheiser HD 800 in balanced mode surprisingly well.
All of this means that the Astell & Kern AK240, owing to its rich and versatile feature set, can easily replace many a home or desktop rig. And simply removing it from its dock will turn it into a stellar-sounding portable rig.
Think about how much you've spent on the various components of your home and portable rigs in DACs, desktop amps, DAPs, portable amps, interconnects, etc. Now imagine replacing all of that with a single well-built and luxurious device... $2,400 doesn't seem that extravagant now, does it?
In fact, this realization got us thinking: how spartan of a rig could we build with an AK240 and still remain satisfied and content? It wasn't long before we both reached a rough consensus.
Warren: I could imagine living happily with an AK240 as the signal chain in my primary rig, with an AKG K812 for home use, an Audeze LCD-XC for office use, and a UERM (Ultimate Ears Reference Monitor) for portable use.
Michael: If I was gonna be away from civilization and I could only take one headphone and one source with me, the AK240 and AKG K812 would be that system.
Looking at the AK240 from this perspective, its value as a personal audiophile convergence device becomes clear. It's nothing less than a Head-Fier's equivalent of a Devialet system. And like a Devialet, the AK240 is a luxury commodity that will never be considered easily-affordable in price.
But it does deliver what it promises to deliver in terms of features and performance. And it has the potential to replace a lot of other gear. This makes it a respectable value in our minds, as long as one has the scratch for it.
Editor's Note: In the days, weeks and months ahead, we expect to encounter a fair amount of doubt, skepticism and incredulity regarding our evaluation the AK240's performance-to-price ratio. However, we invite everyone to use and audition the AK240 for themselves before passing any judgment. After all, had someone told us it was this impressive before we experienced it ourselves, we'd have been unsettled by that news as well.
Concerns & Suggestions
While the Astell & Kern AK240 does a lot, and does it very well, it is not without shortcomings.
First of all, we would like to see a 2.5mm balanced cable adapter included in the box. This would allow us to immediately take full advantage of the AK240's balanced out, without having to source one separately.
Secondly, the AK240 is packed with high-end audio components inside a small metal case. As such, it gets warmer than most DAPs we've tried - with the HiFiMAN HM-901 being a notable exception. There was never any danger of sterilization mind you, nor did the unit exhibit any issues during operation, but it does tend to get warm.
And finally, we have a few personal requests to share from our soapbox...
Michael: This is more of a personal preference than anything else, but I would like to see some full-screen album art, where the navigation buttons only show after a user taps on the screen.
Warren: I would love to see the inclusion of an alarm clock. There are times when we all take music breaks from the stresses of daily life, where we'll drift off into the sound scape of something soothing and atmospheric. I - for one - would appreciate the convenience of an alarm clock, to make sure that I return to consciousness, preferably before I miss an important conference call.
I'm also itching for a theme that isn't so earthy. Three of the the four default themes had a drab olive look and feel to them. The fourth theme includes a brown leather texture, but portions of the interface were still the same drab olive. I hope this changes over time, with downloadable themes added on a fairly regular basis, and I certainly wouldn't mind seeing an theme sometime in the future.
We've been trying to reach for subtlety in wrapping up our impressions, only to be met with futility each time. Since the truth will out soon, especially as more users get their hands on it, we might as well be blunt and reveal our verdict without reservation: the Astell & Kern AK240 is an absolutely phenomenal device that has managed to charm its way past our skepticism and scrutiny.
As an audiophile DAP, the AK240 is superb on every level. Exclusive features like network streaming and instant high-resolution music downloads set it apart from any competing device. It plays every format we're likely to use, while sounding as good or better than any other audiophile-quality DAP we've yet encountered. Its built-in balanced output helps satisfy even the most demanding personal audiophile. It's so easy-to-use that even old geezers can figure it out without much gnashing-of-teeth. And its dual-core processor and customized Android-OS delivers world-class performance and responsiveness while minimizing frustration.
For our fellow enthusiasts out there, each chasing their respective dragons and exploring new horizons in personal audiophilia, we recommend capturing an AK240 as soon as possible. It's the next step along this journey. For newcomers making their initial forays into personal high-fidelity, we suggest starting here with an AK240. Its a complete and competent signal chain unto itself - whether at home or on the road - and it complements a wide variety of headphones and IEMs.
The AK240 is more than Astell & Kern's latest and greatest, and much more than another flavor-of-the-month. It's nothing less than a seminal point in personal high-fidelity. In the years to come, when people look back - searching for that pivotal moment in time where features, fidelity and usability finally came together in a single user experience - they won't be talking about an iPod, or a Walkman, or even a Pono player. It's the AK240 that will be remembered most.
Yes, it's that ******* good.


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@kurochin, seems like you're home free.  The only pause I would have about making it a portable/desktop/office rig is that more demanding headphone may still need amplification.  But if you're going all CIEM, you're totally good to go.  And yes, there will always be a "better" one, but I'm taking a guess that it would be far more expensive as well.  @TurbinePro, it would be quieter.  @Stonemanty, are you listening to the AK240 in balanced mode now?  I just scored a balanced cable with a 2.5mm plug for my UERM at last week's SoCal meet.  Haven't had time to try it out yet, but just thinking about a AK240 --> balanced --> UERM makes me wet.
I read and read and read the reviews of this digital gizmo and I can not find proper specifications for it. There does not seem to be a 'line out' on this player/DAC. Does it have a line out or not ? If 'not' is the case then AK240 demonstrates the clinical insanity of its designers and never mind that it can even brew coffee.