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This is a Review of Astell & Kern AK120ii Digital Audio Player (DAP). http://www.astellnkern.com/eng/htm/ak120/ak120_2_feature01.asp , also available on Amazon: http://www.amazon.com/Astell-Kern-AK120II-Resolution-Player/dp/B00L3NAW42/

Either if you are a novice audio enthusiast or a seasoned audiophile, you are probably familiar with a name of "Astell & Kern". It’s like a fashion brand name or a luxury vehicle known for their stylish looks, durable design, and top of the line performance. Nevertheless, for a number of people A&K products are still an intimidating mystery because of their premium price and somewhat exclusive review coverage. I've read some of those reviews and still had a few unanswered questions, especially what makes this DAP so special at a premium price? As you can see, I've already mentioned “premium price” twice, and I'm only a few sentences into my review. Unfortunately, premium price quite often clouds are judgment since we have high expectations when in reality we are looking at diminishing returns. In the last few years I covered close to a dozen of DAPs priced between $50 -$700, and as a reviewer when you focus on a performance and features it makes it easier to judge a product without a biased opinion clouded by its price, though you still have to consider it. So let me proceed with my review, to share with you what I found, and to let you be the judge if this amazing piece of electronics (oops, a biased slip!) is worth your hard earned money.

People, who appreciate the art of sound or just educated enough to understand that free earbuds supplied with your smartphone or endorsed by celebrities just don’t cut it, are usually in constant search of new headphones to get closer to their ideal sound signature. Unfortunately, a lot of the times we neglect an important variable in this sound signature equation - the audio source. No matter how good you think your iDevice or Android phone sounds, it’s not an ideal source even if you manage to load it with lossless audio files. It will not substitute a dedicated DAP designed with one specific functionality in mind - playing audio without compromises or interferences from 3G/4G radios, noisy power supplies, social media updates, and a ton of apps running in the background. I always looked at DAP as anti-smartphone, and perhaps that’s why I was happy with small screens, hardware buttons, and other mechanical scrolling options. Now, I made a full circle and came back to a product which you can almost call a smartphone without a “phone”.

Arrived in a formally dressed silver carton sleeve, A&K wanted to keep an element of surprise without any revealing glossy pictures or too much of an artwork beside a stamped logo and a company name with a sticker of DUAL DAC on the front. AK120ii is their dual CS4398 DAC version, very similar in looks to AK100ii - a single CS4398 DAC version with a slightly shorter body and a few other cut down specs. On a back side of the packaging you will find a very comprehensive device specification that resembles a typical compact smartphone spec. We are talking about 3.31” AMOLED touch screen display with WVGA 480x800 resolution, 3,250 mAh li-polymer battery, 128GB of internal NAND memory with microSD expansion supporting up to 128GB flash card, Bluetooth 4.0, Wi-Fi 802.11 b/g/n, MTP media device connection, micro USB input, and OTA (over-the-air) firmware upgrade. Yes, we are still talking about DAP, and to reassure that – I removed the sleeve and opened an impressive black gift-box to reveal AK120ii inside of it.

Unboxing.

I have seen pictures of AK100ii/120ii before, but the first hand experience of opening the box and taking a glance at this DAP is priceless. Out of the box I found AK120ii to be surprisingly compact with dimensions of approximate 118mm x 55mm x 15mm and very lightweight at only 177g. Along with AK120ii, included accessories were a high quality usb to micro-usb charging/data cable, clear screen protectors for the front display and the back, a comprehensive quick start guide (printed on a quality paper like it was a wedding invitation), a warranty card, and a fancy leather case. And by fancy, I mean a designer quality "Made in Italy" case with perfect cutouts to reveal all the hardware controls and ports, and to provide a full access to touch screen where only a microSD port was covered. Btw, once fitted, the case is not easy to slide out, but I found a little trick by pushing it out with an eraser tip of a pencil through micro-usb port opening at the bottom. Could A&K have included additional accessories? I certainly would be happy to see more considering the asking price, but optional color leather cases, cradles, and some cables are available for purchase directly from Astell & Kern website.

Accessories.

As I already mentioned, the unit itself felt very compact and rather lightweight despite its solid build and alloy metal housing with a front touch screen. If this would have been a smartphone, I would have already proceeded to power it up, but I was still hesitant holding it in my hand while examining design details. I think the experience of testing and reviewing other DAPs made me appreciate this design even more, including how thoughtfully it was crafted. The ergonomics was perfect for use with one hand, and it felt very comfortable to reach hardware transport controls and volume knob as well as touch screen - not bad considering I have just an average size hands. The transport control buttons are located on the top left side, and you have Play/Pause in the middle between Skip Next/Prev where single click skips a track and a long press fast forwards/backwards. Buttons felt solid, no rattling or shaking, with a very nice tactile response. At the bottom of the same left side you will find microSD slot with a card sitting flush once fully inserted. The bottom of AK120ii has micro-usb connector for charging (impressive battery life of up to 12hrs) and connection to a computer (for a file transfer and use as USB DAC). The top has 3.5mm TRS headphone output (HO which also doubles as electrical/optical Line Out) and 2.5mm balanced output with a 4-pole TRRS connector (for a balanced wired output).

The upper right corner of AK120ii is protruded with a small power button at the top and a dedicated volume knob facing to the right. There is no denial it looks and feels like a real authentic scaled down hardware volume knob you can find in high end desktop systems. The rotation of the knob felt well controlled with a nice feedback, and I was able to adjust it even with a roll of a thumb. I was kind of wishing this volume knob would also function as a push-button control, but it didn’t. I mean, the whole look of the knob design with a cap just screams to be pushed, maybe with some hidden functionality like a quick mute. At the same time, I can understand it would be too easy to accidentally trigger it in your pocket, so this volume knob can only rotate.

Design.

Finally, I was able to tear myself away from pushing the buttons and turning the knob, and went ahead to power it up. Greeted by a glowing “A” logo, it took a little while for the player to boot up. From what I understand, previous AK versions were Unix/Linux based, and the new AK100ii/120ii/240 are Android based for a better support of wireless connection with OTA updates. As a matter of fact, as soon as I booted up and connected to Wi-Fi, within a minute I had a message in notification bar informing me about downloading a system update. It felt like at home with familiar smartphone functionality, especially with touch controls and notification bar. Touch screen was very responsive with every move/slide/touch registering without a lag or a delay, thus suggesting a well optimized custom OS on top of Android. The main screen was well laid out with tiles for Songs, Albums, Artists, Genres, Playlist, and Folder – all corresponding to a specific sorting method of accessing your song library. On top of that there were also tiles for MQS Streaming and Setting. Also, there was an “invisible” Home touch button at the bottom in the middle which took you back to a playback screen. From playback screen, where you have access to touch transport controls and song/album artwork, you can also create a Playlist by clicking on the screen and selecting "+".

The Setting menu was my first stop where you have toggle switches for Wi-Fi, Bluetooth, EQ, Gapless playback, Line Out and Balanced Out selection, L/R Balance, Brightness control, and Theme selection. There was also system settings related to Date/Time, Language, Power management, USB Connection, and Downloads folder. Further in System Info you can keep a track of model and firmware, internal storage management, and SD card management. But I think the greatest feature of A&K OS is how you can access most of these settings from one place in pull down notification bar. It was simply brilliant how you get a bird eye view of all the important settings where you enable/disable it with a simple touch and get into a detailed setting menu by touch’n’hold of the corresponding control. With notification bar accessible from any screen, this was the best and the easiest way to change settings on the fly.

One of the settings I found quite interesting was EQ where you can create a numerous custom presets. Also, you can draw EQ curve on the screen with a finger, and every EQ-band slider will self-adjust in animated fashion following a drawn curve. It was great to see a complete set of 10-band EQ (30Hz/60/120/250/500/1k/2k/4k/8k/16k), but I found it a bit frustrating to adjust individual bands since they were too close to each other to zero in with a finger touch. I would suggest for A&K to implement a zoom-in feature to expand EQ screen for a more precise selection of the EQ band.

In general, it was a pleasure to be able to see song names and artwork, and effortlessly control the playback and selection from a large and clear touch screen without straining my eyes. But it's not only the size of the screen, but how logical everything is laid out and utilized, from pull-down notification bar with access to all the settings, to a "home" button to get back to the playback and the rest of the controls and settings. I also liked how cool it was to adjust the volume once you turn the volume knob and get on-screen volume-arc graphics to slide your finger up/down and also to quickly enable/disable Balanced output. It takes a little bit of time to figure out controls, but afterwards it becomes a second nature to navigate. Going back to my other DAPs after using AK120ii was a painful experience using small screens and clicking buttons to navigate around.

GUI/Interface.

Having an ample storage is very important when you are dealing with high resolution audio and lossless formats, where AK120ii supports everything under the sun. And despite the fact that AK100ii/120ii doesn’t support native DSD decoding (only 240 does it natively while 100/120 converts it internally to PCM), you still will be tempted to load this DAP with your DSD files. Depending on the size of your lossless library, even 128GB of internal storage and another 128GB of external one might not be enough. Or perhaps when you are at home you want to listen to a few other songs/albums without going through a hassle of copying them to a DAP. To expand your storage capacity while you are at home connected to your local Wi-Fi, AK120ii supports MQS Streaming from your local computer. All you have to do is to download a small lightweight MQS Server program to run on your laptop or PC/MAC, select your shared directory, and within seconds it will be mirrored and ready to be accessed from your AK DAP. It’s insanely easy and efficient, and there is no delay or buffering stutter as you streaming the music – sounds just like you are playing it from internal NAND memory. Of course, with a full Android based OS on my smartphone I can also stream anything from the cloud (Pandora, Spotify, Tidal, etc.), but unfortunately you can’t run any 3rd party or even native Android apps with AK120ii. Furthermore, you can also play music directly from your laptop/PC/MAC through AK120ii by utilizing its USB DAC functionality like an external soundcard.

MQS Streaming.

Obviously, AK120ii has an excellent design and one amazing GUI with hardware buttons to complement touch controls, but how does it sounds? Here, I found a few surprises. Keep in mind, the intent of my review was to test AK120ii as a standalone portable DAP rather than a puzzle piece of the equation that requires another $2.5k DAC/amp and $2.5k pair of IEMs to complete a picture in order to make it sound good. I found that it was absolutely not necessary to stack up AK120ii with other portable Amps or to use it exclusively with TOTL multi-driver IEMs in order to enjoy the sound. To my surprise, it paired up quite well with a lot of my headphones straight out of HO, but you have to be VERY selective which headphones to use - everything comes down to finding headphones with a perfect synergy to work with sound signature of AK120ii.

I had a bit of a rough start when I began testing AK120ii only to realize that warm, bassy, and generally v-shaped headphones are not a perfect match for this DAP. I found sound signature of this DAP to be neutral-smooth with a slight touch of warmth. It made my bright and revealing IEMs and Headphones to sound lush and organic while retaining clarity and high level of details. I would even go as far as saying this DAP shapes a sound to be more smooth analog rather than cold-analytical. The background was perfectly black, and I didn't experience any hissing or high level of noise, though my headphones are not that sensitive either. With a help of it's Dual DAC architecture, soundstage had a great level of width/depth, though it wasn't too airy in my opinion. I wasn't able to quite reach that precise level of detailed analytical layering and separation. Don't take this as a negative comment, actually AK120ii was able to breath in a new life into some of my brighter tuned headphones, adding more body and texture making them sound more natural and less fatigue.

As expected, once you switch to 2.5mm Balanced Output and if your headphones can support wide imaging, balanced output did improve soundstage width/depth by further expansion and even some treble enhancement. The difference wasn't exactly night'n'day, but after closer listening it was definitely noticeable, especially with my UM Pro 50 (advantage of replacement cable to go between 3.5mm and 2.5mm was priceless). To get the most out of the balanced output you really need to look into aftermarket quality replacement cables for your headphones. Just a stock OFC or cheap silver plated wires won't be enough. For example, I noticed a better margin of improvement once I switched to low impedance Linum Balanced BaX cable. A balanced wired Whiplash Pure Silver cable (part of modular system) did introduce an improvement as well, but hearing my UM Pro 50 or W40 or A83 with Linum Balanced BaX took it a notch higher, which I attribute to lower impedance of Linum Litz cable.

Speaking of headphones I used for testing, I picked Pro 50 since it has a darker/warmer signature, while W40 is smoother and brighter, and A83 hybrid delivers revealing bright upper mids/treble thanks to BA drivers balanced out by dynamic driver covering low end. I also used ATH-MSR7 since these full size cans deliver a high-res extended and detailed sound and not as forgiving when it comes to bright recording. With AK120ii a performance of all these headphones was very consistent and sound became very smooth and organic in upper mids and treble while still preserving high level of detail retrieval. It's very interesting how with the same CS4398 DAC used in Hidizs AP100 DAP and FiiO X3 2nd gen as well as AK100ii/120ii, due to variations in low path filter and voltage/current amplification there is a difference between colder analytical bright sound of AP100 vs smother warmer sound of X3ii vs analog-smooth detailed sound of 120ii. Of course, you do need to try different pairs of headphones to find a match with a better synergy. When it comes to low end (bass), AK120ii favors headphones with more quality than quantity. A sound with headphones that have a typical v-shaped signature and exaggerated bass spilling into lower mids will become muddy. Even a more controlled low end of UM Pro 50 with stock cables (or Pure Silver cables) wasn't shining until I went through cable-rolling to find a better match which turned out to be Linum Balanced BaX. In there I found Linum to be a better match to open up the sound with even more details and soundstage expansion, while their new prototype of Super Balanced BaX impressed me a lot with a smoother balance of low end.

Even so I'm not a fan of EQ tweaking and hate how other DAPs usually have one custom preset option, being able to have numerous custom presets you can name according to your pair of headphones was very convenient with 120ii. I was actually pleased with sound shaping after EQ adjustment where frequency boosting didn't introduce any unnatural harsh artifacts. YMMV since its a matter of a person taste, but I just wanted to make a point that you can sound-shape any pair of headphones to make them work with AK120ii.

Another great way of sound shaping is to pair up AK120ii with your favorite portable amp while bypassing the internal one. I really felt like a mad scientist playing with all these combinations of headphones, cables, and amps - but it turned out to be quite a rewarding experience. I know I already mentioned that my review intent was to see how it performs standalone without any external stack up, but I was actually able to shape a sound other than with EQ by pairing it up with two of my favorite amp (FiiO E12A and Cayin C5). These both amps did take a bit of an edge off analog warmth in comparison to 120ii internal amp, but they also introduced more byte to the sound with a different texture at low end and brighter crispiness at top end. Especially C5 added more analytical clarity to upper mids and a touch more details while brightening the treble, though I personally liked the "looks" of 120ii stack-up with E12A.

I'm sure a lot of you will be curious how does $1.7k DAP compares to other cheaper DAPs I tested in the past. I know the sound quality is very important, but when it comes to A&K DAPs you have to look at the whole picture where overall experience plays a significant factor. It probably sounds very cliché and some of you might think I got spoiled by having access to test and to compare different DAPs, but it's an important point where you can forget for a minute a price tag and just focus on the product's sound, ergonomics, flexibility, and control interface. All I have to say is that experience of testing and reviewing AK120ii ruined the enjoyment of my other favorite DAPs. Maybe it's a temporary infatuation since I spent the last few weeks mostly using this A&K DAP, but I felt that a touch screen interface made such a perfect sense in song browsing, playback control, and overall settings - I actually became a bit frustrated with a button clicking or a wheel scrolling to get to where I wanted in other DAPs. And this touch screen interface was not a reminder of a "smartphone", absolutely not! It enabled me to be in full control of how I wanted to listen to my music, and I found that to be quite liberating.

Nevertheless, if you compare it to other DAPs like for example Cayin N6, those who are after a lush organic sound will prefer A&K sound signature, while if you want a more analytical detailed sound - N6 is a better candidate. In my opinion, they both are relatively neutral, but AK leans more toward neutral-smooth with a touch of warmth, while N6 leans more toward neutral-bright with a slightly better retrieval of details. With something like FiiO X5, I hear X5 being thinner, more neutral, less dynamic (sound is a bit flatter), and soundstage being narrower. Especially with X5 (single DAC architecture), you can hear an advantage of dual dac design of AK120ii and N6 where the width/depth of soundstage along with airiness and improved separation/layering becomes more apparent.

Next to N6, X5, and X3ii

Conclusion.

I mentioned early that I took a pricing out of the equation, just focusing on design and performance. I guess in a conclusion with my traditional "Overall" statement, I should put this variable back in and look from a perspective of the overall AK120ii value. I have reviewed a lot of DAPs and various stack up combos of my Note 4 with portable Amps or usb otg DACs, thus I tend to believe I have a good base for comparison. With that in mind, I still feel that Astell & Kern delivered a product that took the best out of all that audio equipment and encapsulated it in a very compact Digital Audio Player with the most logical touch and hardware controls I have experienced to date. It looks solid, it feels solid, and with a right pair of headphones it sounds solid! I know some people expect $1.7k DAP to sound 2x as good as $800-$900 DAP, but you have to keep in mind that with TOTL audio equipment (just like with multi-driver IEMs) you are in a territory of diminishing returns. Can Astell & Kern keep this crown forever? Only time will tell since we are facing a number of new TOTL DAPs from other manufacturers planned for this summer, and I know that competition will heat up! But I can tell you with certainly, A&K set a very high bar (and not just in pricing) where all my upcoming reviews will be measured against this little masterpiece!