Between first and second-generation Astell&Kerns, Sony launched the NZW-ZX1 Walkman (AU$699). It’s the flagship portable player in their hi-resolution audio assault.

And it’s tough to ignore the physical similarities between the second generation AK120 (AU$2099) and the NXW-ZX1. The Sony unit is roughly the same length and width as the AK120 II but it’s thinner. It’s lighter too: 135gm vs 170gm. In the pocket the Sony is less noticeable.

A protrusion found on the rear’s lower-third houses the Walkman’s amplification circuits. This makes for a neater fit in the palm of the hand but also trickier to strap it to an external DAC/amplifier, a problem compounded by the need for an additional cable that’s sold separately. Sony have gone their usual route of substituting the industry standard – in this case micro USB – for their own connector.

A cable for re-charging and data transfer is supplied and this Walkman will reportedly run for ~30 hours on a full battery – that’s quite a bit more than the iRiver-descendent. My daily use of both units over a 4-week period confirmed the Sony as the longer lasting of the two by some margin.

Connect the Sony to a Mac or PC and it auto-mounts its internal storage as ‘WALKMAN’. Getting songs into its ‘Music’ folder is a drag-and-drop affair. Transfer speeds are faster than the AK120 II and Mac users are mercifully spared the Android File Transfer app required by the South Korean rival. Storage isn’t expandable on the Sony – an internal 128Gb is all you get. For some users, myself included, that’s plenty. If you need more then go for the Astell&Kern player.

Screen wise, the Walkman’s larger 4” (854 x 480px) trumps the 3.31” (480 x 800px) of the AK120 II. Colours are more vivid on the Sony but it won’t hold a candle to modern smartphones. The Japanese unit has a more responsive interface and speedier library scans its rival.

The Sony’s sound signature is clean, crisp and zippy with few concessions to warmth. There’s some grit and glower in its treble that makes detail retrieval and rhythmic snap appear more overt; putting the same shoe on the other foot, the Sony sounds slightly less refined and thinner in the mid-bass than the AK120 II.

Next to third party DAC/amplifiers like the ALO International+ and (even more so) the Chord Hugo, the Sony can, at times, sound a little brash. That’s a lemon-sharp reminder that you can’t have everything at this price point.

Matching headphones must be chosen with care lest an overdose of metallic tinge on cymbals presents on less-than-optimally recorded source material like the boisterous barroom rock of The Hold Steady’s Teeth Dreams.

A more even tonal balance arrives when this Walkman is paired with warmer, meatier-sounding models: think V-Moda Crossfade M-100 and Master&Dynamic MH40. I really hit pay dirt with Xiaomi Piston 2 universal IEMs whose balmier sonic signature played counterbalance to the Sony’s audible eagerness. (Side note: at $30 on eBay, these Xiaomi IEMs are one of the biggest bargains in head-fi right now).

Whilst at the Sony table during May’s Fujiya-Avic headphone in Tokyo, I let the NZW-ZX1 play solo before having Sony’s PHA-2 intercede with D/A conversion and amplification. The additional portable amplifier plays closer in style to the Astell&Kern units but reservations remain about dropping this much cash on the Walkman for it only to serve as transport. If you’re dropping AU$699 on a portable player the last thing you want to hear is that it needs another similarly priced brick to make it sound good!

If all this sounds like I’m being hard on the Sony DAP, I’m not. The NWZ-ZX1 not only offers PCM file support up to and including 24bit/192kHz but it sounds MUCH better than your iPhone and (especially) latest Samsung Galaxy and Google Nexus models. The Sony has ‘My First DAP’ written all over it.

Central to this Walkman’s interface is the bespoke music player that allows for library browsing via your music’s meta data (if it’s there) or folder structure (if it’s not). There’s also a very cool cover art view that presents your albums as vinyl strewn across a floor – yes, you can slide them around.

Sony’s DSEE (Digital Sound Enhancement Engine) promises to “high-range sound that is lost during compression for a pure, natural quality. It also upscales compressed audio to a quality higher than that of CDs, so you'll hear clearer, more energetic sound.” You can’t put back what’s already been stripped out or what was never there in the first place, can you?

Where the NWZ-ZX1 really leaves all other rivals for dust, including the Astell&Kerns, is connectivity. Can you read and write emails on your A&K? Facebook on your FiiO? Check Instagram on your iBasso? No you cannot. With the Sony unit running a modified version of the Android operating system, you can. Think of it as an Android phone without the phone and camera.

Sony provides firmware updates using the Walkman’s Wi-Fi connection. That’s useful for adding new features. A 300Mb download and a reboot took my review unit from v1.12 to v1.13 (which added DSD playback). Given the current paucity of legally available DSD material for the contemporary music fan, this feature went untested. As most digital audio products, especially those aimed at the man in the street, the main consideration remains CD quality audio, especially in the context of what follows…

If you can work a smartphone you’ll have zero problems using the NWZ-ZX1. With an Android O/S and Wi-Fi at your disposal, the Google Play Store is your oyster.

The aforementioned music player app includes an option to ‘Throw’ audio to any DLNA receiver on your home network. That’s the KEF X300A Wireless for this fella. It’s a super-handy feature to have at your disposal if you want to quickly jump from headphones to loudspeakers. Also present on the Sony is Bluetooth for slinging music to any appropriately equipped loudspeaker e.g. UE Logitech Boom. NFC allows for single-touch Bluetooth pairing.

The speaker built into this DAP is probably no bigger or better than that of your average smartphone but enabling the Clear Phase setting during playback makes it sound a smidge more acceptable. I’d only use this feature once all other playback possibilities have been exhausted.

When at home, Orange Squeeze is my app of choice for browsing music stored on an Antidpodes DXe device. Being a VortexBox-based device, SqueezeBox Server indexes the library. The ability of Orange Squeeze to wirelessly copy any album from the server to the control device with a single click is a more convenient way of getting music on the Sony player, obviating the need for the USB cable.

Even those without dedicated music servers can benefit from wireless file transfer. Files can be transferred from computer to Walkman over the air with apps like WiFi File Transfer Pro.

Of course, cloud services eventually come screaming into view. Find yourself at work and wish you’d dropped Pink Floyd’s Animal’s onto the Sony before you left that morning? No problem. Fire up the Spotify app to download it for offline listening. Don’t like Spotify’s MP3 encoding? Grab yr Floyd fix via the Tidal or WiMP app instead. Lossless audio takes longer to download but it’s worth the wait on the Sony.

In Tokyo’s Yodobashi Camera, Sony’s black and gold ‘Hi-Res Audio’ logo can be seen at every turn. One thing’s obvious: this Japanese giant are putting all they’ve got behind increasing the mainstream uptake of sample- and bit-rates higher than Redbook CD’s 16bit/44.1kHz. And that’s kind of ironic given this player’s major talents are with supporting Redbook sources.

Overall, I prefer the sound of the AK120 II but the some of its advantages over the Sony are neutered by its comparative lack of flexibility. The NWZ-ZX1 has me listening to a broader selection of music. I take it with me more often than I do the Astell&Kern but in doing so I’m forced to be more selective about headphones before heading out the door. Know that neither player is suited to doing proper justice to the likes of Audeze or MrSpeakers; for more demanding loads you’ll still need a separate amplifier.

The final word goes to geographical pricing. At AU$699, Australia is roughly on par with Japan (Y62,980) and Amazon.com’s US price of $629. All of which are a whole lot cheaper than the UK whose residents are asked to stump up a whopping £549 for the NWZ-ZX1. That’s AU$990 at current exchange rates.

For more information visit Sony Australia.

About the Author

John is the publisher of Digital Audio Review, covering news and reviews of interesting and affordable hi-fi equipment. John is also a staff writer for 6Moons and TONEAudio