Astell&Kern AK120 Portable Media Player

November 2013

Reviewers' ChoiceAstell&Kern AK120Portable audio has pretty much been anathema to me, with the exception of a long stretch in the 1990s when I flew around the country to give guest lectures and poetry readings, accompanied by a Sony Discman and a bulky wallet full of CDs. Even now, I don’t jog to the beat of Bruno Mars from an iPod, nor do I cruise through campus with cables dangling from my ears like strings of white tears. Mainly, I used to just listen at home to my reference system or not at all -- unless I had to fly somewhere. Then, I’d plug a pair of Monster Turbines into my iPhone and listen to uncompressed files for however long the flight took, as much to shut out the jet noise and conversations around me as from any wish to hear music. To me, listening this way was not real listening, but a way to pass the time and to keep the outside world from passing through me. Personal audio was a barrier, a kind of wall shored against my ruin.

The Astell&Kern AK120 media player ($1299 USD) has dramatically changed all of that. I take it with me when I jet around, but also find myself using it after arrival -- say, in a European café having an espresso and a cigar -- as well as after my return home, when reading in my study or working at my desk. This player, whose manufacturer claims produces Mastering Quality Sound in a portable package, has introduced me to a new world of pleasurable listening. Premiered at T.H.E. Show Newport Beach 2013 and released early in that summer, the AK120 is one of the sweetest audio gizmos I’ve ever come across.

Early this summer, I took the AK120 on a trip to Prague, where I was teaching, using it first on the long, mid-leg plane flight from San Francisco to Frankfurt, then for the next three weeks in the subways of the Prague metro, late at night in my Vinohrady apartment, and knocking about the quaint and historic streets of Mala Strana and Stare Mesto, in the Golden City on the banks of the Vltava. Then, in August, I took it along on a month-long retreat to an artist-residency program next door to Neil Young’s ranch in the Santa Cruz mountains of Northern California. The AK120 was a superb audio companion, easy to use, and so compact -- about the size of a pack of Gitanes cigarettes, it fit nicely in my pants or shirt pocket. I had my tunes wherever I wanted, in high-resolution and Apple Lossless, too.


An upgrade of the 32GB, single-DAC AK100 ($699), the dual-DAC AK120 holds 64GB of audio files via its internal memory; 128GB more can be added via two 64GB microSD cards, for a total of 192GB. Those two DACs are Wolfson WM8740s, which can handle any of the standard formats -- WAV, FLAC, WMA, MP3, OGG, APE, AIFF, ALAC, AAC -- and, via new firmware released in July, DSD.

The AK120’s compactness, and its ergonomically intelligent design, make it attractive and pleasing to use. It measures 3.50”H x 2.33”W x 0.57”D and weighs only 5 ounces. Its case is of brushed, anodized aluminum with an elegant hairline finish. On it are a 2.4” QVGA touchscreen, a small analog volume-control wheel, and three tiny buttons for back, forward, and play/pause. Across its top are the earphone/optical-out terminal, an optical-in port, and the power button. On the bottom are a micro USB port and, behind a sliding door, the slots for two microSD cards. It all slides neatly into a carrying case of Italian leather. Like a Porsche for portable audio, the thing just oozes righteousness, compact power, and ease of use.

Setup and operation

Setup was pretty much a snap. After I’d installed iriver plus 4, the AK120’s music-managing software, loading audio files was just drag and drop. Hi-rez files take up a lot of space, though -- I filled up 64GB pretty quickly, loading full symphonies, concertos, and other complete discs (I don’t listen to “songs”). After I got back from Prague, I bought a 64GB microSD card from Amazon and quickly loaded it with another 50GB worth of files (mostly 16/44.1 ALAC, which take up much less space), so I’d have even more music on my writing retreat.

Charging up the AK120 the first time was tricky. It turned out that my sample may not have fully charged when I first tried to do this, by hooking it up to my iMac overnight a few days before the flight to Prague. I was later told that charging slows or stops altogether when the computer goes into standby. Iriver’s technical support team advised me to instead use an iPhone charger, which has a higher voltage than my computer’s USB 2.0 port and can’t go idle. But throughout the review period, I never seemed to get the promised 14 hours of playback time. My norm was about six hours, and sometimes less -- disappointing. Iriver told me that higher-resolution files, screen brightness, and higher volumes all shorten battery life -- but still, four to six hours seemed very low.

Accessing FLAC or ALAC files was never a problem, but, in early August, after iriver’s release of new firmware that made the AK120 DSD-capable, I had trouble finding some DSD files I’d bought from After a few tries, I managed to download the firmware and install it successfully in the AK120, but the DSD files didn’t show up in the AK120’s normal Albums menu. I had to go into Folders, then Music, and page through the list of all the hi-rez files (mostly FLAC) I’d stored there. I was told that iriver would soon have a fix for this.

Astell&Kern AK120

Handsome as it is, the AK120’s leather case caused two problems. Despite a precise cutout for them, the advance, pause, and back buttons on the AK120’s left side proved difficult for one-handed operation because of the leather’s thickness. I had to hold the AK120 in my right hand and work the buttons with my left forefinger or thumb. Then, the right edge of the case, which frames the touchscreen, physically blocked the AK120’s screen-controlled, fast-scroll slidebar. I learned to scroll up and down by lightly and delicately touching the Album menu screen to skootch and tease it through the files. This often resulted in the inadvertent selection of a file I did not want to play, at which point I had to hit the back arrow to return to the Album menu and again begin the touchy, hair-trigger, hop-skip-and-drag scrolling process, which was slow, jerky, and annoying. In short, the leather case effectively defeated the AK120’s fast-scroll function.

The touchscreen itself was wonderfully intuitive and easy to operate, sensitive even under its protective film. It was charming to see album images pop up as I made selections. The AK120 conveniently organizes files under six menu headings: Songs, Albums, Artists, Genres, MQS, and Folders. MQS means Mastering Quality Sound -- that’s where you store your hi-rez files. Settings are accessed via an icon on the Home screen: you’re given a menu for Date and Time, Languages, Display, Power, Bluetooth, and Advanced. Advanced includes a Tutorial, System Info, Auto Library Scan, Lock, and Reset. It was easiest to use Albums to page through my files, which were automatically alphabetized by album title. And, while playing, it was much easier to use the touchscreen arrows for back, forward, and pause/play than the control buttons on the left side.

A design feature I immensely liked was the sleek, slotted “shoulders” around the volume control, which protect it from both accidental damage and inadvertent rotation. How often have you placed a portable device in your pocket, only to find that the volume dial has rubbed against a set of keys, and you jump out of your skin because the volume’s suddenly gone crazy? Well, the chances of this happening with the AK120 are almost nil -- a nice touch. The volume wheel itself worked flawlessly -- it was easy to spin, yet calibrated, and with enough resistance to stay where you’ve set it. As you change the volume, white numerals (0 to 75) flash across the screen.

Throughout the summer, I used a pair of Cardas EM 5813 Model 1 earphones ($425), another new product that debuted at T.H.E. Show Newport Beach 2013. Uncomfortable with their stock eartips of rubberized plastic, I swapped them out for Comply foam tips, with which I could listen for hours without discomfort.

Late in the review period, I also used a pair of Audeze LCD-3 headphones ($1945, review forthcoming), the AK120 driving them to good levels with most music. In order to make things work, I used a Cardas HPI mini-to-female 1/4” adapter cable. However, I frequently had to dial the AK120’s volume up to within three or four full clicks of its maximum setting of 75 in order to get a decent volume out of the hard-to-drive Audezes, which have low sensitivity -- something else that shortened battery life. My reference Sennheiser HD 650 ’phones, also fairly insensitive, fared similarly in terms of volume.

Although the AK120 is touted to play all standard formats, I tested it only with FLAC, ALAC, and DSD files.


The AK120 sounded unfailingly rich and resolving, with clean highs and a gorgeous midrange. Bass could sometimes be diffuse on airplanes and subways, but, in the main, the AK120 was great with orchestral music, opera singers, jazz, rock, and anything else I threw at it. Much better-sounding than my iPhone 5, it made all listening pleasurable and involving.

Women’s voices, such as those of operatic soprano Renée Fleming and jazz singer Diana Krall, sounded superb even in “Red Book” resolution. Both sounded clear, extended, and with great microdynamics and a smooth midrange. There was absolutely no etch or raggedness, even in prolonged coloratura passages high in Fleming’s range. Krall’s voice came through with all its characteristic bounce and tease, its sensitive shades of emotion and shifts in timbre.

Male voices, too, sounded great. Among those I listened to were João Gilberto, Paul Simon, the operatic bass Peter Harvey, and the inimitable George Benson. The essential aspect of each of their vocal characters came through, from Gilberto’s dry nasality in “The Girl from Ipanema” (24-bit/96kHz FLAC, Verve) to Simon’s sweet and tender poignancy in “The Boxer” (24/96 FLAC, Sony). But it was Benson’s virtuosity in his breakthrough version of Leon Russell’s “This Masquerade” (24/96 FLAC, Warner Bros.) that knocked me out. His singing style is a complex hybrid of jazz, pop, and personal swagger. His wide range, full of numerous shifts in interpretive timbre, climbing glissandos, and his signature scatting that doubled his speedy flat-pick runs on electric guitar, just never really came through with any digital version of this recording that I’d heard -- the original LP, Breezin’, has been my reference. But hearing the classic tune in 24/96 was a revelation. The AK120 captured the soulful, dynamic quality of the music and all of Benson’s bravura vocal style so well that I felt myself wanting to sing along in-flight, surrounded by the plane’s sleeping passengers.

Wind instruments sounded wonderful, from the astonishing tenor saxes of Stan Getz and John Coltrane to Gerry Mulligan’s mellifluous baritone sax and the agile clarinet of Benny Goodman (all 16/44.1 ALAC). But it was with piano music that the AK120 really strutted its stuff. Via my iPhone, pianos always sound distorted to me, the bass keys loose and rumbly, the upper registers tinny and ragged. Through the AK120, Alfred Brendel’s piano in his recording of Beethoven’s Piano Concerto No.1 with Simon Rattle and the Vienna Philharmonic (16/44.1 FLAC, Philips), and Glenn Gould’s in his recording of J.S. Bach’s The Goldberg Variations (24/96 FLAC, Sony), were always crisp and crystalline in the highs, tight and without echo or rumble in the bass.

In other recordings, massed strings sounded pleasing and sweet, warm in the midrange with open highs, even at 16/44.1. Orchestral music, previously banished from my portable listening -- it’s hard to take the iPhone’s edgy highs in the strings, the constant glassy tone -- became a great pleasure via the AK120. The bassoon in Adoration of the Earth, from Stravinsky’s The Rite of Spring, performed by the Budapest Festival Orchestra under Iván Fischer (24/192 FLAC, Channel Classics), sounded warm and full, with a pleasing resonance. String attacks were unfailingly speedy and dramatic without edge or glassiness. And the brass fanfares presented brilliant, precise timbres in a tonal palette full of varied colors.


I’ve had the iPhone 5 for about three months, and took it along with me to Prague and my writer’s retreat. The iPhone 5 generally has lots of presence and an “up-front” sound. Sonic immediacy is its forte, with a touch of distortion and an overdriven quality its obvious drawbacks. Listening to “The Girl from Ipanema” (16/44.1 ALAC, Verve), there was a kind of cabinet-sounding resonance to Gilberto’s slightly nasal voice, and Astrud’s had a trailing echo, as though from a studio box. Getz’s tenor-sax solo and accompaniment sounded big and forward, with touch of grain in the highs. And the strummed guitar sounded boxy, with an echo-chamber effect. Not all of this was unpleasant, but it didn’t compare to the sound of 24/96 FLACs via the AK120.

Listening to the FLAC download through the AK120 with the same Cardas EM 5813 earbuds I used with my iPhone, Gilberto’s voice sounded much smoother and not so nasal. The rhythmic guitar chordings were better damped, the sound emphasizing more the strings than the instrument’s body. Astrud’s voice was completely clear. Getz’s tenor produced more harmonics and had a sweeter tone in the lows, with no after-notes or sonic shadows, as with the iPhone. His higher notes were more extended and without grain. Getz and Astrud’s interplay in the duet had much more tonal differentiation between his tenor sax and her alto voice. Part of the pleasure of using the AK120 was in recognizing how plaintive is Astrud’s singing, vs. how robust and nimble are Getz’s accompaniment and solo. Finally, with the AK120, the rhythm section produced a sweeter groove, sounded more together, and contributed subtle crescendos throughout the track that weren’t apparent via the iPhone 5.

Through the iPhone 5, opera singers like Renée Fleming sounded recessed rather than forward in the mix, noticeably more ragged and less pure in their sustained notes, with an odd quaver that was not vibrato but a timing issue. Orchestral strings were glassier, with a very evident echo in tuttis that smeared bass-drum strokes. The difference in the sound of Brendel’s piano in Beethoven’s Piano Concerto No.2 (ALAC 16/44.1, Philips) through the iPhone and the AK120 was laughable. Brendel’s arpeggios across the midrange distinctly rumbled via the iPhone 5, and there were other distortions. His trills and highs had a slight reverb and were never crystalline. As with opera singers, there was a quavery quality to Brendel’s instrument that told me the playback was completely mistimed -- it sounded almost like a fortepiano. The AK120 was much cleaner in sound, with black backgrounds, no quavering, and no “after-noise” hissing or grittiness. The iPhone’s soundcard just could not compare with the AK120’s dual Wolfson DACs.


One night in Prague, I went to the Stavovské Divadlo (Estates Theatre) to hear the Mozart Requiem performed by a summer orchestra and choir. The Stavovské is where Mozart’s operas Don Giovanni (1787) and La Clemenza di Tito (1791) were premiered, the latter staged in celebration of the coronation of Emperor Leopold II. For authenticity, the opera scenes for the Miloš Forman film Amadeus were shot at Stavovské, as it’s the only theater still standing in which Mozart once performed. The theater is tiny by contemporary standards -- I estimated about 400 seats, perhaps 250 in the orchestra and another 150 in the tiered boxes rising above where I sat, about mid-hall. This theater is intimate -- although I sat in only the tenth row, there were only six rows behind me, and the orchestra felt and sounded as if it were in my lap. The concert was magnificent, the conductor taking a slow pace reminiscent of Otto Klemperer’s, the orchestra performing with snap and precision. From the beginning, I heard the sound as completely sumptuous, grave and sublime; then each note from each instrument took up its own color, texture, and impact, each section of the choir and then each soloist was distinct -- yet by midway through the score, the full sound of the orchestra and singers together overtook all details to create instead an experience that was emotional, uplifting, and very difficult to describe. I could say it was “memorable,” except I could not clearly recall any single aspect of it to talk about. The music had left thought and even memory behind, and resided in my memory of the deep feelings the music evoked in me.

Astell&Kern AK120Afterward, as I tried to recall individual passages of Mozart’s great work, I could not. So, as I rode the subway to my apartment three stops away, I resolved to listen to it again, through the AK120. Just before I’d left for Prague, I’d downloaded Jos van Veldhoven and the Netherlands Bach Society’s recording of the Requiem (24/192 FLAC, Channel Classics). Listening to it risked obscuring my emotional impressions of the concert in exchange for the focus on specifics of the recorded version, but, more than anything, I wanted to use the AK120 to revive my appreciation of this music. It proved excellent for this. In the Introitus, for example, because in the recording I could hear the choir’s sopranos, altos, tenors, and basses inhabiting an ethereal zone spread behind and above the orchestra’s period instruments, my recollection of the acoustic of the Estates Theatre came back. There was more ambient information at the concert, but I was conscious of more details of performance in the recording, in which I could also hear layerings: altos above left, sopranos above them, tenors and basses poking out here and there from spots at the middle rear. At the performance I’d reacted more viscerally, without the level of detailed awareness made possible by the AK120. In the Lacrimosa from the same FLAC file, the double basses laid out a warm, resonant foundation, pulsing with authority under the choir and violins. And the timpani had wallop, punctuating the score with gravitas. My recollection of the performance became thus interfused with the fine playback by the AK120.

I found myself in love with both types of listening, and -- like the Chinese Taoist philosopher Chuang-tzu waking from a dream and not knowing if he was a butterfly dreaming he was a man or a man who had dreamed he was a butterfly -- in the end, I could not separate these competing impressions. They merged in a common love of the music. It’s a testament to the AK120’s capabilities that its sound brought me more appreciation for the Requiem rather than failing to persuade me of its verisimilitude in such close comparison to the live concert. It’s that good.

I found the Astell&Kern AK120 indispensable for portable listening -- it sounds great with all types of music, its dual DACs providing fabulous resolution, speed, and great timing. While I can’t quite say it matches live performance or even the sound of my reference system, it nonetheless makes possible reference-quality personal listening. My weeks of intense use of it while traveling have confirmed iriver’s claim that the AK120 provides Mastering Quality Sound. I don’t see how I can ever do without it. I’m buying one.

. . . Garrett Hongo

Associated Equipment

  • Media player -- Apple iPhone 5
  • Earphones -- Monster Turbine, Cardas EM5813 Model 1
  • Headphones -- Sennheiser HD 650, Audeze LCD-3
  • Accessories -- Cardas HPI-A headphone adapter, Comply foam eartips

Astell&Kern AK120 Portable Media Player
Price: $1299 USD.
Warranty: One year, limited; 90 days, accessories; 30 days, refund or exchange.

iriver Inc.
39 Peters Canyon Rd
Irvine, CA 92606
Phone: (949) 336-4540/4541
Fax: (949) 336-4536