There is no doubt Astell&Kern has been one of, if not the leader, of portable digital audio players (DAPs) in recent years. While their products have always started at over $1000, with their new top-of-the-line AK380 (reviewed) coming in at $3500, today they are playing the other side of price extremes. From the eye-poppingly priced AK380 reviewed earlier, this review concerns Astell&Kern's new $499 AK Jr. We all know technology always gets better, cheaper, and smaller. Thinking back to the old Osborne 'transportable' computer during the early 1980s, it had only 64 kb of memory, a built-in 5.25" monochrome screen and 1200 baud modem. The Osborne was a technological masterpiece at the time and weighed a hefty mere 23.5 lbs. To put this into perspective, your cell phone has about the same size color touchscreen, a massive improvement in processing power and gargantuan memory storage capability by comparison. In addition, today we have Internet speeds in the Mbs.
Astell&Kern's AK Jr greatly benefits from many years of extensive research and continual development. Over time, technology trickles down and today the AK Jr is the company's entry-level digital audio player that builds upon everything Astell&Kern has learned over the years. It has a bright 3.1" 240 x 400 pixel resolution LCD touchscreen that is said to be about 1.4 times larger than their original AK100 produces a few years back. AK's lil Jr is also thinner, lighter and handles all the usual digital file types including lossy MP3, lossless FLAC and Sony proprietary DSD. DSD (direct stream digital) is converted to PCM (pulse code modulation) so it is not handled natively for you pesky sticklers out there. If implemented correctly, which is not that hard to do nowadays, DSD (DFF) to PCM is fine by me. It is how the unit sounds, not what it can and can't do natively, that matters.
Internally, Astell&Kern's AK Jr uses the Wolfson WM8740 DAC chip. While the higher end models by the company use two or more DACs for balanced processing, within this elegant and slim design they choose a great sounding single chip solution. There is no dispute by audiophiles and portable audio enthusiasts alike that Wolfson has been producing excellent sounding DACs for many years. Bluetooth version 4.0 provides a wireless connection, yet with some loss of sound quality of course because that is the nature of the Bluetooth beast. There is no Wi-Fi and thus you can't access music within, for example, your NAS drive or cloud storage. Fortunately, Astell&Kern's AK Jr comes with 64GB of memory internally and has a slot just above the right side volume knob for a microSD card. You can easily insert upwards of a 200GB card to expand music storage capability. Of course you can carry multiple microSD cards and swap them. I'm waiting for the 512GB microSD card ($1000!) to come down in price since 128GB cards are getting to be pretty cheap today, and will be cheaper tomorrow, and throw-aways in a decade. Well, it is better than when I paid $80 for an 8MB memory card (not a typo, it was indeed $10 per MB) for my digital camera years ago. So see, technology gets better and cheaper over time.
With a relatively healthy built-in stereo amplifier, the AK Jr has a maximum output level of 1.95 Vrms at a low impedance of 2 Ohms. All of my CIEMs including the UE 18 Pro, Noble Kaiser 10, and both JH Audio's JH-13 and Roxanne were easily able to reach ear-bleeding volume levels. The OPPO HA-2 also reached satisfyingly high output volume. This includes using my typical car audio 'basshead' tracks, since deep bass notes are the most power hungry frequencies within the audio spectrum to reproduce acoustically. Unlike lesser devices such as your cell phone, you have an abundant 152(!) steps of volume control via the touchscreen or the right side volume control. Turning the round dial one click moves the volume in 0.5dB increments and a finger flick gets you about 6 clicks. When the touchscreen is on, you can drag your finger to the right to turn down or left to turn up the volume level at a faster rate than the right side hardware control.
Even with the OPPO HA-2 at full volume output I could not detect any dynamic compression, which can happen when an amplifier circuitry runs out of reserves. Speaking of audio output, you can also go into the Settings menu and choose Line Output to change from headphone to Line Out. This is great when you want to use the unit in your car, a home stereo system, etc. As longtime readers know, portable audio players always find their way into my car audio system via Kimber Kable's superb GQ MINI-Ag 100% silver connector.
Another great feature of the Astell&Kern AK Jr is the ability to be used as a 24-bit/96kHz external DAC for your computer. It is easy to hook a standard USB to micro USB cable, included with the Jr, from your computer to the AK Jr. Then press the touchscreen choice Connect To USB DAC and CAH-CHING you're in external DAC mode so that the sound from your computer comes through the AK Jr. Also, when you hookup the USB cable to your computer the touchscreen also allows you to choose between just charging the battery or connect as a removable disc. Connecting as a removable disc allows you to transfer files from your computer to the AK Jr's memory.
With a slim and elegant design measuring a mere 2.08" x 4.60" x 0.35" (WxHxD) and weighting a paltry 3.45 ounces, it is extremely easy to put the AK Jr within your pocket without feeling like you have an ass wart or carrying a brick. While lightweight, the unit feels very solid and built for action. The aluminum body has slightly curved edge sections and looks great without a 'Hey look at me" shout-out like other players. For the paranoid types out there, you do get a few screen protectors in the box, plus a USB cable and manual. Astell&Kern's AK Jr does not come with a case or ear buds, yet you can order some great cases right now from Analogue Seduction online in a wide variety of colors and styles for around $40. Astell& Kern has cases available in six different colors for $50.
Astell&Kern AK Jr Sound Quality
Quiet. Even with the efficient Noble Kaiser 10 there was zero hiss or background noise. Nada, none, zilch! When changing tracks there was nary a click, pop or extraneous noise. It was pure music, and here is where I'm starting off by saying that 'jump at you' dynamics were impressive for such a tiny and inexpensive device. Obviously Astell&Kern put quite a bit of effort within the Jr's analog output stage. Since we're on dynamics, micro dynamics are very good and big audio pyrotechnics are most impressive. Whilst not the best I've heard at any price, and remember I've played with the $3500 AK380, have the $2500 AK240, $1200 Sony NW-ZX2 and many others here, for $499 I was hearing far more dynamic shading with oomph and power than was expected. At this price range, engineering 'corners' need to be cut. Yet when it comes to the important amplification section within this lil AK Jr am hard-pressed to say much of a cost-savings was involved other than the Jr being unbalanced versus the additional costs for supporting circuitry and DACs needed for balanced output.
I used the impressive JH Audio Roxanne with stock cables (waiting on the Double Helix silver version) and accurate Ultimate Ears 18 Pro custom plus my fave of the bunch Noble Kaiser 10 to really get a good feel here of this DAP. Astell&Kern's Jr is neutral to a small teeny tiny touch of warmth. DAPs like the Sony NW-ZX2 produce a richer harmonic tapestry, which can be a good thing for cheap and cheesy universal ear buds / IEMs and certain bargain-priced headphones. Speaking of headphones, of course the OPPO HA-2 were put through the paces and with the AK Jr it solidified my highly positive review of these headphones. Getting to the down 'n' dirty of it, harmonically Astell&Kern struck an excellent balance of accuracy without the music being strident or annoying. In fact there were times music was more enjoyable over the AK Jr versus the over twice as expensive Sony NW-ZX2. The $499 AK Jr crushes the $300 Sony NWZ-A17SLV when it comes to a low-priced unit you can listen to hour after hour imho.
For you PRATaholics, here again we once again find ourselves in the neutral, balanced, to slightly groove side of things. PRAT, for those unfamiliar, is Pace, Rhythm And Timing. Call it groove or funk factor if that helps ya. Furthermore, and I'm kinda jumping ahead a bit here within this review, as the superb inner resolution and dynamic shadings play extremely well together to produce PRAT at this price level. It is those very critical subtle-yet-audible timing cues playing their part of the music's whole. Ok, guess it is time for me to write about the Astell&Kern Jr's resolution.
Color me impressed! For half a kilobuck you get a remarkable amount of resolution. This is no doubt in part to their choice in DACs, and the Wolfson is highly desirable by audiophiles and music lovers alike for good reason. When combined with the very fast and clean amplification section within the Astell&Kern AK Jr, I feel you are getting around 90% or more of those top players for about one-fourth the price. Almost want to say 95%, yet am waiting for the AK380 to arrive here, which after multiple listening sessions at shows sounds to be the new reference unit in achieving the ultimate in portable music playback. In addition, the whole scale of what is possible at a given price point is moving higher with each passing year, no make that month, as new DAPs become available. Ah yes, this is one of the many difficulties, pitfalls if you will, of being a longtime high fidelity audio reviewer. What we felt was reference-level three years ago are now normal for mid-priced products.
Overall resolution is remarkable. It does an inspiring job at unraveling intricate passages yet keeping their independent volume and stereo image within the textural seams of the music intact. It is not up there with the AK380 or to some extent the Sony NW-ZX2, yet far better than I recall with the lower priced Sony NWZ-A17SLV and, dare I say this, perhaps better than my original AK120 (read: not the newer II version, which is not in-house for testing/comparo). You get an excellent dose of resolution and hints of what you can expect within Astell&Kern's higher priced offerings like the AK240 and reference-grade AK380. Seen below is a size comparison of all Astell&Kern digital audio players, with the AK Jr being to the far left.
For you bassheads, there is a good amount of drive and power behind the deepest of bass notes. It is not bedrock solid like the AK380, and not augmented like the Sony NW-ZX2 when you use the Clear Bass equalizer setting, yet you get resolution and cleanliness over low frequency pyrotechnics. Astell&Kern's AK Jr resolved my basshead car audio FLAC tracks during those Miami Bass Wars days, yet does lack that last 15% or so of solidity as the sound 'drops off' a bit below 40 Hz. It is a slow roll-off to my ears, yet I'd prefer this over more bass yet with distortion. Yes you can still hear the deep bass, yet it seems to lack that last bit of torque 'n' grunt to pull things through at full force. So it's there and relatively accurate, just not fully amplified by a nearly endless foundation as I recall with the $3500 AK380. Compromises at $499 had to be made and, glad, they kept it on the side of accuracy versus throwing more, usually flabby and bloated, bass at your ears. Please keep in mind I'm talking about the very deepest of bass that most songs have zero of. It is a type of torture test, frankly, as I feel a reviewer must take everything into account to fully test a product at all extremes.
High frequency extension is smooth and clean, yet not the last word in stratospherically delivered. Drum cymbals, bells and upper reverb within recordings have far more delicacy than I was expecting from a player at this price level quite frankly. Midrange is also outstanding and well-balanced within the overall musical presentation. Yeah, I keep saying a balanced sound, yet it is the word that keeps sticking within my head. Goldilocks would love the AK Jr because everything from the price / performance is just right to my ears. There is no doubt in my mind the AK Jr is a lil overachiever; sounding far better than expected in many ways. Ok, so neither are reference level, yet you get so very much for $499 it makes me reconsider the laws of diminishing returns. Perhaps chalk this up to trickle-down technology combined with Astell&Kern's many years of experience and know-how.
Notes Between The Notes And Some Car Audio Tunes
Within my high-end car audio system the Sony's DSP and soundscape was more evident than with headphones and CIEMs. In addition, the Sony's Clear Bass combined with Sony's DSP gave the car a more involving experience (for me). Darude's song "Sandstorm" is a classic and with the Sony I feel like the car is a rolling dance club, whereas with the AK Jr it has an audible flavor closer to that of a recording studio. No doubt the Sony's overall DSP combined with their Clear Bass equalization, which helps to synthesize bass notes, is more like a dance club. With jazz and classical music this effect is less so with the Sony and thus closer to how the AK Jr sounds, yet with what I'll call TiŽsto... Say the following words out loud when you read it: Boots-n-pants -n- boots-n-pants -n- boots-n-pants -n- music... the Sony is more enjoyable in the car. I wanted to love the AK Jr playing through the car audio system, yet couldn't quite get there with dance, dubstep and the like. This is most definitely a personal preference and choice of music style. With classical, jazz and rock music there was less of a decisive preference of one portable music player over another. The really big difference is phasing and soundscape in the car, as the Sony just sounds ever so more enveloping whereas the AK Jr is like your typical German high-end automotive system versus, say, one that is British. Car audio and general automotive reviewers agree that the British sound systems are better than their German equivalent and I'm not one to disagree here.
Another situation pointed out by those who already have the unit is the stuttering and hiccupping of the graphical user interface (GUI). While I'm sure a firmware update can solve this issue, it does need to be said that with firmware 1.02 there are times the unit is slow to respond to your finger touch when scrolling, etc. In fact on my test microSD card for review/torture testing there are folders with quite a few 'mixed media' songs that include FLAC, WAV and DFF files. Yesterday, the Astell&Kern AK Jr came to a virtual halt-stutter-halt whilst I was trying to access a specific song within a folder. Am sure a firmware update can easily solver this, so we're all just going to have to wait for the solution. In fact I was holding off publishing this review for a week or so in hopes new firmware would be released. Another problem that crops up is the sensitivity of adjusting the volume level on the touchscreen, as it is easy to go from low to full with a finger slide/move for someone like me. Thus be very, very careful and move your finger s-l-o-w-l-y and in very small amounts across the touchscreen or you'll find yourself being at near zero or near full volume before you know it.
Of course what really
matter is if the music is enjoyable, and here we have a winner! There's always a
delicate balance between extreme accuracy and musicality. It is not that they
are mutually exclusive, yet at this lowish price level it becomes far more
challenging. Astell&Kern has done an excellent job with the AK Jr. This extremely lightweight and small DAP
allows you to bring great audio anywhere, anytime, and
will deliver many hours of musical delight. I keep looking at this tiny player
and admiring how big it sounds, with plenty of output for all my CIEMs and the
OPPO HA-2 headphones. Big, beautiful sound within such a small package that I
never felt was possible. Bravo Astell&Kern, you've got another winner on
your hands! As always in the end what really matters is