The Astell and Kern AK100 Digital Audio Player

The Astell and Kern AK100 is a trendsetter. While a few other high-end digital players have cropped up here and there to combat the giant grip that Apple has secured, very few have made the impression on the industry like iRiver’s steadfast extension into the luxury DAP has in the past year. With an ever-expanding product line, it appears that the Astell and Kern is very happy with the results. This year the company announced the original AK100 ($799) will be joined by the pint sized AK10 and even more recently, the flagship AK240.  Add in the AK120 and Astell and Kern give you portable high fidelity at nearly every price point. Others companies are noticing as well. Calyx should have a player out later this year called the “M” that should compete with the AK120/240 and HifiMan continues to expand its line both budget and premium directions.


The 2.3 x 3.1 x .5” size is totally usable for true portable listening and even working out. Running with the AK100 tucked into a pocket didn’t prove to be a burden in least, an amazing complement to a pair of high end CIEMs. The aesthetics are very refined, and the touch interface worked without a hitch.  While the touch screen may not be quite as slick as Apple’s, this reviewer found it fully usable and very easy to navigate. The physical volume knob that sticks out from the side of the unit feels much more secure than your usually timepiece adjuster, but its responsiveness to volume control could be a little tighter. My preference is a quick dissention with slow upward increases, but at times it felt that quite a bit of scrolling had to be done in order to get it to the place I wanted it to go, especially when unitizing a variety of headphones with varying sensitivities. Interestingly enough, volume control is not restricted to only the external knob, adjustments can be made directly on the touch screen at any point when the volume screen is up. It may seem a bit odd at first to have a knob sticking out of the side if you are used to the Apple experience, but physical volume control is always an extremely welcome interface, and a preference of mine for listening sessions. The physical buttons located on the left edge of the brushed aluminum frame are also a nice addition and handy to use.  Track selection up and down and play/pause can be controlled with these side click buttons which makes it very easy to adjust your full listening experience without ever having to pull the player from your pocket to look at it (very nice feature for running). In your hand the unit feels like a fine and refined piece of craftsmanship. Its glass-like texture on the front and back feels quite soothing against your palm and the overall design looks like a team of accomplished individuals spent some time on its creation.

Here is a rundown of the specs from the company site:

  • Display – 2.4inch QVGA (320 x 240) IPS Touchscreen
  • Supported Audio Formats – WAV, AIFF, FLAC, ALAC, APE, MP3, AAC, WMA, OGG
  • Sample rate – 8kHz ~ 192kHz (8/16/24-bits per sample)
  • DAC – Wolfson WM8740 24-bit DAC (High-End Audio DAC)
  • Decoding – Supports up to 24-bit / 192kHz Bit to Bit Decoding
  • Charging Interface – Micro USB Type-B
  • Interface – USB 2.0, OPTICAL IN/OUT, Headphone Out
  • Dimensions – 2.33 ” W x 3.11 ” H x 0.57 ” D
  • Weight – 4.3 oz
  • Feature Enhancements – Firmware upgrades supported

It’s worth mentioning that Astell and Kern decided to go with the Wolfson WM8740 as their opening DAC chipset. The AK120 sports the same chip, but but configures it for dual mono with a chip for each channel, a total of two in the device. The flagship AK240 moves over to Cirrus Logic silicone, with the top-of-the-company’s-line CS4398, again in a dual mono setup.  The CS4398 is the same chip used in Leckerton Audio’s portable DAC/Amps, the UHA760 and UHA-6S.MKII (review upcoming). The unit features two micro SD card slots that support up to 32GB each, which will no doubt be nearly essential with all the super high resolution files that can be played on the device.  The AK100 comes standard with 32GB of internal storage. Connecting the unit to your computer brings up two options, charge battery or connect removable disk.  So while the unit is quite seamless in its file transfer capabilities, there doesn’t seem to be a way to incorporate it as a true external USB-interface DAC. The mini-optical jack located next to the headphone output will allow for both sending and receiving of a digital signal, but this type of execution seems to adhere its usefulness to only a small handful of situations of users stuck in the situation with optical only digital feeds. But at its core the AK100 is a portable digital audio player, and should be viewed as such.

The Sound

The acoustic delivery from the AK100 is something that you really can’t prepare for.  Nearly thrice the price of the leading consumer digital player (which is more likely than not a phone these days) demands that some noticeable penance be paid. Sonically this DAP forgives all the audiophile sins of inflated price points. The leading edge of this superior sound quality is driven by an amazing and deadly-silent background. Its aural soundscape bounds off a canvas so dark, it makes all the stars in the universe visible. This in turn leads to some very positive outcomes including better detail retrieval and superior dynamics. It is the absolute king when it comes to finicky custom In-Ears. For the price, which includes player, DAC and amplifier, the AK100 is perhaps the best CIEM combination you can currently get under a $1k by a country mile. When it comes to headphone selection however, the Kern doesn’t leave the big boys out in the cold. The internal amplifier was able to drive the planer magnetic LCD-3 and LCD-XC from Audeze to respectable levels, although you may want to look into an external amplifier to push many of the hard-to-drive headphones that grace the head-fi hobby (like the HifiMan HE-6). As a source in such a situation, the AK100 continued to deliver accurate, transparent sound through its headphone output (set to the maximum). Astell and Kern have even been known to run loudspeaker setups with the portable unit as a source at audio shows with impressive results. When it comes to its intended use however, the AK100 is truly at the top of its game. Paired with the Audeze LCD-3 the fidelity conveyed from solid recording strikes you in the head with authority. The LCD proved to have great synergy with the AK100. Jason Mraz’s album Love is a Four Letter Word delivered an exceptional exhibition of focused treble, rich mids and impeccably tight lows with amazing extension.  Tracks like The Freedom Song provided plenty of bass slam and instrument separation without ever getting remotely close to congestion during some of the busy, information-intensive sections of the song. This hyper-accuracy gives the overall texture and tone a slight tilt towards the technical over warmth. Again, the silence between the notes is something that sets this particular unit’s sound apart from so many other systems. It really makes the dynamics pop and detail stand out.

The original AK set the stage for everything that has come after it. It is truly a portable piece that everyone needs to give a listen at least once. Considering its price point, the AK100 can still be the “go to” player for those who want superior sound over Apples offerings, but don’t want to contend with the accelerated pricing of the latest crop of flagship audiophile offerings. Astell and Kern has really laid down the formula for success with the launch of this product. The touch screen interface is simple and easy to navigate and is well complemented by its double-up physical counterparts. It is the reference for custom In-Ears under a grand. The black background is the stuff legends are made of and its fidelity gives many full sized systems (that cost much more) a run for their money.  Highly recommended.

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