Sonny and I both thought it was about time I reviewed my AK240 on the site, seeing as it is my personal reference and it does hold a coveted position on the Inearspace Pride Of Place.

So as I’m sure you are aware this is Astell & Kern’s flagship portable music player placing itself above the newest AK120 II (1499) and the AK100 II (£799). They gave the AK240 the tagline of “The Ultimate” (cringe alert), which is a big claim indeed, but then for £2200 you really would expect this to be the “ultimate” DAP (digital audio player) experience.

Here is a quick overview of the AK240. This is a portable music player capable of converting WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF and DSF files. From 16/44 all the way to DSD128 the AK240 is capable. It makes use of two Cirrus Logic 4398 DAC chips (one per channel) and an XMOS chip for native DSD conversion. It has a 256GB flash drive and a micro SD card slot for up to 128GB. The chassis is machined from aircraft grade duralumin (yes they have just announced a stainless steel version). The product has a 2.5mm TRRS balanced headphone output as well as a 3.5mm single ended headphone output, plus the previously mentioned 3.5mm headphone output doubles up as a SP/DIF optical output and all these jacks are on the top panel of the product. The unit weighs 185g approximately and uses a 3250mAh 3.7V lithium polymer battery. There is a gold version (more expensive), a Bluenote version (blue with 75 Hi-Res albums) and soon to be an AK240SS, which utilises stainless steel housing, will also be a little more.

Phew that lump of info is over.

I must mention something quickly, with amps, DAC’s Headphones, earphones, customs or even computer source programs the feature that takes the biggest percentage of importance by an absolute landslide is sound. Without a question sound to me is the most important. BUT with DAP’s there is a lot more to it. I need a DAP to have great sound as well as a good UI, battery life, ergonomics, memory, file support etc.

So for this to really be my “Ultimate” it had to really impress.

The Features

Screen: First off let’s have a look at the screen, and it is actually really nice, the resolution is 480×800 which might be nowhere near full HD but on a 3.31-inch AMOLED screen it’s really not too bad at all. Album covers are detailed enough and I’ve never thought, “hmmm, I wish the screen had better resolution” and I can’t see anyone wishing for more to be honest.

Memory: This is really important for a DAP capable of literally every file format from MP3 to DSD because of course DSD takes up a huge amount of space, as does Hi-Res but not to the same extent. The 240 has 256GB of on board storage with the opportunity of expanding this by 128GB via Micro-SD increasing the total to 384GB. Now this might be considered pretty big and for a portable device and yes it is, but I think they have missed a trick by removing the second SD slot that was present on the previous players, 512GB would, to me, have been the way to go, especially as they have shown they can put two SD slots in a product.

Battery: This is an area that still divides people’s opinions. The 3250 mAh battery, which is bigger than most mobile phones by the way, gives between 8-10 hours of battery life depending on what you are listening too. DSD is a bit of a battery drainer for sure; there is no way you are getting near 10 hours if you are listening to it. Another thing I do to maximise my battery is reduce the brightness and ensure the Wi-Fi and Bluetooth are turned off when not in use.  With these settings and the DAP on shuffle I get between 9 and 10 hours while using the balanced out. I consider this to be pretty darn good but as it is a time value I’m sure you will all decide for yourself.

Line Out: One area I think the AK has a slight flaw is with the “line out”. My issue is that it isn’t actually a line out, but a pseudo line out that is simply the amp section set to max volume. Using a true line out would allow the connection to another external amp whether it is portable, desktop or Hi-Fi without double amping. Going directly from the DAC section of the product would give a more direct un-interfered signal path. I really do think a true line out would be beneficial. That being said we have used the line out with portable amps and into HiFi systems via a pre-amp and have always been happy with results.

Balanced Output: On to the balanced out of the 240, the 2.5mm TRRS is a connection I did not have before, so I enlisted the help of Effect Audio with a couple of IEM cables from them with this termination. Having compared quite a bit, I have to say, there is very, very minimal difference between the two connections. With IEM’s I would struggle to tell the difference on an A/B. Having said this when using the HD800 via the plus sound 2.5mm balanced cable I did think the balanced sounded a touch smoother and fuller, with better driver control, due to the higher output.

Aesthetics and Ergonomics

Striking, would be the first description of the appearance from me but I love it. The aggressive lines, the sharp corners and the bulk of the unit itself make it look like a real quality bit of kit. The carbon fibre insert in the back is absolutely stunning too. It’s not just the general appearance that impresses though. It’s the finish of the thing too. Believe me when I say I have searched for imperfections and little machining errors and there are absolutely none, not a single out of place mark anywhere, the knurling on the volume pot is great too, real impressive quality. Even the carbon fibre is super consistent and really very good (unlike the carbon fibre case of Sonny’s JH Audio Roxanne).

Now, looking at the 240 you might think how the hell is that going to be comfortable in the hand and how easy to use can it possible be, but let me tell you the shape of this product is perfect IF YOU ARE RIGHT HANDED. As one side of the product has exaggerated bezels it sits perfectly in the palm and absolutely wonderfully for controlling both the screen and the volume. I can see though, that if you are inclined to hold the player in your left hand this design is obviously less ideal.  I will just mention that I have noticed the 240 to get pretty warm both when on charge and while playing for long periods, especially when in the pocket.

It really does feel perfect to me though, especially with the beautiful Minerva leather case. I do have a very small criticism of the volume pot though. It feels a little bit flimsy, a bit weak and easy. This phenomenon is often referred to as knob feel and it is something that I think everyone will understand. This knob feel just isn’t right for me I would like it a touch stiffer and a bit more solid. That would be perfect!

The UI (User Interface)

This is a really important area in a DAP and one that I feel the previous generation of AK’s suffered in. They were sluggish and certain actions were simply not available such as a home button, search bar etc. I speak on behalf of all the new AK products when I say that this UI is a really big improvement. The fact they chose to base the UI on android has meant that they have been able to layer up an already proven base for portable devices. It still has the AK feel to me, but it is far smoother and way more intuitive than before. My favourite new feature without a doubt is the search bar. Oh my god I used to get frustrated with this on my PWAK100-S. Searching and looking for music by genre, and file formats is pretty cool too! Oh and the drag and drop playlist feature is again really quite nifty. Seriously though it’s clearer, more responsive, easier to navigate and just far more professional looking. Its obvious Sonny is envious of this, as he has to put up with the old UI, ahaha!

Home Screen

Play Screen

Search Function

Album List


All these craftsmanship efforts and software developments are all fantastic but how does it sound I hear you ask? Is it as good as the hype suggests? In a word, yes but it’s not going to be for everyone and it is improvable for sure. Let me explain.

This player is an extremely neutral sound but I would describe it as a little clinical occasionally, it is not a warm or coloured player in any way, it is flat and it is a reference sounding player; it’s not necessarily a feature that will always benefit your listening experience. It is seriously revealing. If you feed it MP3’s or any other compressed file it destroys them it really shows up all the flaws and negatives of compression. Even badly recorded stuff of high bit rates get exposed. I would much rather listen to a well recorded CD rip than a 24/192 badly recorded track and the 240 just exaggerates every flaw in the recording.

This does mean though that for all of us lucky enough to have some beautifully recorded music library whether they are CD rips or DSD128 files it is a truly joyous experience. Bucket loads of detail are layered wonderfully to give a really 3D presentation. Separation is awesome and imagery is just the same and even with IEM’s as sensitive as the Vision Ears VE6 the background is really quiet, the noise floor is really low, although I have to add it is not quite as quiet as the Vorzuge Pure. This has the effect of making you feel really immersed in the music, a tricky thing to achieve from such a personal way of listening to music.  You could say that I’m pretty in love with this thing.

Top end is amazingly detailed, extended, and massively airy. Mid-Range is beautifully focused, detailed and never grainy. Bass is agile, full of detail and not bloated or unsure. Bottom end could have a little more impact and a touch more decay for my preference but this is me really nit-picking here. Super impressive across the board really.

To truly appreciate the AK240 you need a great library of source files and a great pair of earphones. Yes earphones. The amp stage doesn’t have the power to drive 98% of your favourite open back cans and when I say “drive” them I don’t mean ‘get them loud’. That’s not what it means. I mean power to control the drivers properly and allow them to move and reproduce sound to their full capabilities. My laptop output can get a HiFiMAN HE500 to loud volumes but it doesn’t drive them properly. That’s the story here. It does lack a little power but then its size doesn’t exactly suggest it’s going to be a 2 watt per channel power house now does it?

It is worth a quick mention that I did use the HD800’s balanced via a 24awg, type 6 litz, cryo treated copper cable from PlusSound a really well made cable actually, feels lovely and the Aluminium Y split means that it really feels like a quality cable. Anyway, the HD800’s actually sounded pretty nice, not at their potential from a desktop rig at all but considering it was a little portable box they sounded pretty good indeed. Nice and spacious and well resolved, not peaky or overly bright, something they are rather prone to. But we are never going to recommend this as a dedicated source for them, especially un-amped although if you happen to have a pair, it is certainly not an off limit combination.

You would be absolutely correct if you were thinking I am besotted with this thing. It is great, but there is just one small thing I would like to say.

As many of you know Sonny uses his PWAK120B and his Vorzuge Pure as his IEM rig for on the go and it’s really a fantastic sounding combination but really quite a different sound. I don’t think the detail retrieval or spaciousness is as astonishing as they are on the 240, but there is one area the 240 gets trounced. And this area is dynamics. The macro details and dynamic ability of Sonny’s rig is amazing and the 240 come nowhere near. As I say they are very different sounding rigs, but if you are someone that digs huge dynamics and scaling there are alternatives if you are willing to go through a lot of hassle.


The AK240 has achieved the title of best sounding DAP if money is no object among a lot of people and a lot of groups. Its sound is technically brilliant and to some people will be close to perfect. But if you are after a warm, luscious, coloured sound this might not be to your taste.

I assure you though if you listen to it and hold it you will appreciate what an acoustic achievement this is as well as an achievement in design and quality. It’s a special item indeed.

In the UK it’s too expensive, it’s actually stupidly expensive in the UK at £2200 or at today’s exchange rate $3310 USD… this is the biggest downside to their entire range of AK products in the UK not just the 240. You guys reading in the US, feel lucky for the prices you get, even if still not cheap.

At the moment in my findings, it is the best sounding DAP on the market but we had the Lotto Paw Gold arriving on our doorstep and that may well prove a match for the mighty 240 so we shall see what happens! Although that is of course a story for another day and another review.

To finish then, if money isn’t a problem it is amazing, a really wonderful bit of audio equipment that deserves its spot on the Inearspace Pride Of Place.

Josh Coleby