The Astell & Kern AK UW100 are made to deliver eloquent, revealing and engrossing sound – as long as your ears are big enough, and you don't mind the lack of active noise cancellation.
Dynamic, detailed and utterly convincing sound
Decent battery life and call quality
…except big ‘buds won’t suit little ears
No voice control
No active noise-cancellation
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Astell & Kern AK UW100: One minute review
The Astell & Kern AK UW100 are the debut true wireless headphones from one of the true heroes of portable audio – or, at least, A&K is a true hero as long as you’re well-heeled enough. Its portable digital audio players are without peer, but unless you’re prepared to spend a significant amount of money to find out, you’ll have to take our word for it.
The Astell & Kern AK UW100 earbuds aren't quite as stratospherically priced as its music players, but they’re nevertheless priced to meet the best true wireless earbuds for audiophiles head-on. And while in some ways they’re specified more impressively than the models they want to usurp, in other features they lag behind somewhat.
But if you value pure sound quality over having a check in every box on the spec-sheet, the UW100 are approaching ‘no-brainer’ status. In audio terms they’re high up among the most accomplished true wireless earbuds around – in every meaningful sonic respect, they impress. Detailed levels, dynamism, soundstage, tonality, attack, you name it.
The UW100 are impressive across the board, and as long as their physical dimensions and weight (both of which are a bit above the average) don’t put you off, they absolutely demand to be tried.
Astell and Kern AK UW100: price and release date
- $299 / £249 / AU$399
- Released in April 2022
The Astell & Kern AK Hi-Fi TWS UW100 (to give them their full and massively unwieldy model name) true wireless in-ear headphones are on sale now. In the United Kingdom they’re priced at £249, while in the United States they go for $299. In Australia you’ll need to part with AU$399 to secure a pair.
It hardly needs saying that this is serious money where true wireless earbuds are concerned, and any number of alternatives from any number of extremely well-regarded brands can be yours for very similar outlay.
Accomplished specialists including (but not restricted to) Bose, Bowers & Wilkins, Grado, Sennheiser and Sony all have acclaimed models ready to go toe-to-toe with the UW100. Heck, even Apple has a dog in the fight.
In short, then, Astell & Kern couldn’t really have picked a trickier party to attempt to crash. But it came prepared.
Astell and Kern AK UW100: design and features
- Some specification highlights, some specification omissions
- Relatively large and weighty
- Good battery life, rapid charging
You’ve got to hand it to Astell & Kern. In a product type where ‘design’ takes a back seat to ‘function’, it’s not only managed to make the UW100 look a bit different but it’s managed to make them look like an Astell & Kern product. The angular ‘shadow and light’ design is immediately recognisable from the company’s digital audio players.
This very welcome touch of individuality doesn’t come for free, though. The UW100 are fairly big earbuds by prevailing standards, and at 7g each they’re far from the lightest around – Apple AirPods Pro are 5.4g each, but comparison, which makes a big difference. Still, the choice of five different sizes of ear-tip in the box means getting a comfortable and secure fit is no problem.
As befits a company that likes to overspecify wherever possible, Astell & Kern has gone to town where the most important elements of the UW100 are concerned. Wireless connectivity, for instance, is via Bluetooth 5.2 and includes support for the aptX Adaptive codec. Incoming digital audio information is dealt with by a high-performance AK4332 32-bit digital-to-analogue convertor that is (unusually in products like this) separated from the Bluetooth chipset. And once digital has become analogue, sound is served to the wearer’s ears via a pair of balanced armature drivers supplied by specialist Knowles.
Battery life is a very respectable six hours from the earbuds themselves, plus another three full charges in the (necessarily chunky and equally distinctive) charging case. Should you manage to go a full 24 hours without visiting a charger, a 10-minute pit stop will hold you for another hour. The UW100 support wireless charging via any Qi-certified pad, as well as USB-C connectivity.
Unlike pretty much every rival (except, notably, the Grado GT220), the UW100 don’t feature active noise cancellation. The company is bullish about the effectiveness of the passive noise isolation these earbuds provide, but it seems likely that any number of prospective customers will see this as a shortcoming.
Mind you, Astell & Kern is so convinced of the passive noise blocking efficiency from its eartips here that it provides four stages of ‘ambient mode’, accessible via the control app or the capacitive touch-surface on the earbuds themselves, to allow you to hear the outside world. The UW100 use a mic array supplied by Alango to boost external sound, as well as to ensure crisp, coherent call quality.
What those mics don’t do, though, is interact with any voice assistants – control is strictly via the touch-surface on each earbud. Oh, the control app is useful for checking on battery status, selecting between five EQ settings, rearranging the functions of the touch-controls themselves, and choosing the level of ambient sound you want to hear (or turning that function off altogether) – but as far as actually controlling playback goes, it’s touch-controls or your source player. That’s your lot.
Astell and Kern AK UW100: audio performance
- Lavishly detailed, especially in the midrange
- Big, believable and absorbing sound
- Passive noise isolation is less successful than audio performance
Put simply, the Astell & Kern UW100 are excellent-sounding earbuds, able to hold their own against the very best around (which for me, at least, as far as pure performance goes, probably means the Grado GT220).
The sonic talent that’s on display here is profound. The most immediately impressive aspect of the way the UW100 sound is probably the midrange reproduction: it’s detailed to an almost unlikely degree, able to reveal the barely there information and most fleeting transients in a vocal performance. John Wayne Gacy, Jr. by Sufjan Stevens sounds immediate, intimate and thrillingly realistic – the close-mic’d recording of his voice means the Astell & Kern are able to reveal the tiny secrets of his technique, breath-control and phrasing, as well as some minute wavers at the end of notes that lesser earbuds simply aren’t alert to.
Acoustic design: Closed
Weight: 7g per bud, 65g case
Drivers: Knowles balanced armature driver
Battery life: 6 hours (earbuds) 24 hours (charging case)
Extra features: Touch controls, iOS & Android control app, aptX Adaptive
And once you’ve assimilated this frankly startling level of midrange fidelity, the rest of these earbuds’ talents come into focus. The UW100 are a spacious, open listen, and create a soundstage that’s defined, separated and focused all at once. There’s width and depth to the Astell & Kern presentation, a space for everything and everything in its space. But the unity and coherence of an overall recording is never ignored – in fact, it’s emphasised. And the result is a sound that’s simple to follow and examine in forensic terms, but equally easy to enjoy as a consistent and convincing performance.
From the solo piano of Nils Frahm’s The Bells to the ‘everything including the kitchen sink’ overload of Kate Bush’s Sat In Your Lap, the UW100 are a vivid and persuasive listen. Bass is deep, clean and controlled, packed with harmonic and textural information, while at the opposite end of the frequency range there’s enthusiastic bite – but with the substance and, again, sky-high detail levels to prevent it becoming hard or tiring. The entire frequency range hangs together smoothly, with no areas given undue prominence.
Dynamic headroom is considerable, so when a recording really attacks where volume is concerned the UW100 track it faithfully. The harmonic variations apparent in unaccompanied piano are identified and delivered, but not overstated – the Astell & Kern simply give them the weighting they deserve, and as a consequence they sound wonderfully natural.
Downsides are few, and none of them have anything to do with the sound the UW100 make. Astell & Kern’s claims for the potency of the passive noise isolation are rather overstated, for example: the UW100 do negate a degree of external sound, but anyone expecting performance on a par with an ANC system will be underwhelmed. And while suppression of noise during calls is reasonable, it’s hardly class-leading – you'll want some Bose QuietComfort Earbuds for that.
That’s it for grumbles, though. The Astell & Kern UW100 are supremely accomplished true wireless earbuds, and they’ll have you listening to familiar recordings as if it was your first time.
Should I buy Astell and Kern AK UW100?
Buy them if…
You’re here for the sound quality
The UW100 can go toe-to-toe with the best-sounding earbuds around.
You like a statement product
No one will confuse your earbuds for any others.
You’re not that chatty anyway
There’s no voice-assistant functionality here.
Don't buy them if…
You prefer silence
The UW100 isolate you from external sounds, but only up to a point. These are not noise-cancelling buds.
You’re fortunate enough to have petite ears
These earbuds will suit the larger-lugged.
Think the Astell & Kern AK UW100 aren't right for you? Here are three alternative true wireless earbuds that might be just what you're looking for.
Bowers & Wilkins PI7
Sticking with companies that use ampersands, these are wonderful-sounding wireless earbuds for audiophiles that actually include active noise cancellation too. It's not especially powerful ANC, but it'll make music more audible in busy locations for sure. These are also pretty chunky in design, and fairly expensive, but like the UW100 they're very much worth it.
Want elite sound for a slightly lower price than the UW100? These are still premium, but will save you a tidy sum, and you get active noise cancellation, praising the value even further. They're less pretty, but you won't care once you hear the sound quality.
Cambridge Audio Melomania 1 Plus
Think all these headphones are just too expensive, but still want sound aimed at audio purists? The Melomania 1+ are small buds with the best sheer sound quality for the price, no question. You don't get noise cancelling or any other bells and whistles here: they're all about making awesome audio affordable.
First reviewed: April 2022
Simon Lucas is a senior editorial professional with deep experience of print/digital publishing and the consumer electronics landscape. Based in Brighton, Simon worked at TechRadar's sister site What HiFi? for a number of years, as both a features editor and a digital editor, before embarking on a career in freelance consultancy, content creation, and journalism for some of the biggest brands and publications in the world.
With enormous expertise in all things home entertainment, Simon reviews everything from turntables to soundbars for TechRadar, and also likes to dip his toes into longform features and buying guides. His bylines include GQ, The Guardian, Hi-Fi+, Metro, The Observer, Pocket Lint, Shortlist, Stuff T3, Tom's Guide, Trusted Reviews, and more.