Astell & Kern UW100MKII Review

Astell & Kern UW100MKII Review

There aren’t many names that elicit the same level of quality as Astell & Kern. Their high-end digital audio players are top-of-the-line, and other accessories they’ve made like the HC2 have met that standard easily. They’ve also released Bluetooth earbuds in the past with the UW100, and now there’s a new version of that very model. The UW100MKII is A&K’s latest true wireless earphone, promising high-end sound. Does it surpass the previous version?

Astell & Kern UW100MKII box

What You Get

  • UW100MKII Earbuds
  • Charging Case
  • 4 sets of ear tips
  • USB Type C Charging Cable
  • User Guide
  • Warranty

Astell & Kern UW100MKII single

Look & Feel

If you’ve seen the original UW100, then you shouldn’t be too surprised by the design of the MKII. It retains the same shell and basic construction, with A&K’s identifiable edged design. From the looks of the earphones shell, it doesn’t look like something that would fit comfortably in your ear, but I found them to sit quite naturally. When worn, the UW100MKII is barely noticeable, offering a good seal and great support.

Astell & Kern UW100MKII charging

Design & Functionality

Within the UW100MKII is a single full-ranged balanced armature, which has been upgraded with adjusted positioning within its newly designed acoustic chamber. There’s also a high resolution DAC capable of 32bit sound. The ANC has been given an upgrade too, with stronger isolation that eliminates more intrusive noise than before. This still isn’t the most efficient ANC in this price range, but it works well enough to do its job. You can also download the A&K Control app to play with different ambient modes, as well as EQ. Lastly, the UW100MKII has touch-sensitive controls that can be used to activate playback. These controls have a very long delay and sometimes have trouble registering properly.


The UW100MKII uses Bluetooth version 5.2, supported by a premium tier QCC5141 chipset. Paring is lightning quick, and throughout many hours of listening I never experienced any dropouts.

Battery Life

Off a single charge, the UW100MKII should last you through about 9.5 hours of playtime. When you include extra charges from the case, the total become 29 hours of battery life. This is exceptionally large for the price, and can last you through a few days before needing to charge the buds again.

Astell & Kern UW100MKII pair


With the A&K name, you expect a certain quality of sound, and that’s reflected in the soundstage. The UW100MKII matches the level of width and depth you get with many wired IEMs in this range. Its wingspan is noticeably larger than many true wireless earphones in this price range, properly adhering to left/right stereo positioning. It’s strict in its linearity, but that doesn’t take away from the fullness the spatial imaging provides. Instruments and effects have a good scale and appear realistically within the soundstage. The separation also adds layers to each performance, giving them enough space to express their contents.

Low End

When called upon, the bass of the UW100MKII can offer some great force. Most of the time, the low frequencies sustain a reserved response but then showcase a more dynamic performance where impact is needed. There’s always a surface of bass detail that feels natural in the mix. It then smoothly transitions into reproducing more-bodied bass textures that have a gratifying groove. Here, the bass exhibits more coloration, with quick and punchy tones to enjoy.


With most sound elements, the midrange performs at an admirable level. Nothing is left in the background, as the mids provide plenty of room for full instrumentation and vocal expression. In fact, the vocals were a consistent highlight of this sound signature, supplying more accented details and transparency. Everything in the midrange responds concisely, bringing a form of accuracy to the sound signature that you won’t hear often with true wireless.


While they’re not as emphasized as certain bass and midrange frequency clusters, there’s a clickiness to the highs that feels very satisfying. They aren’t given the most significant gain, but they balance well with the rest of the sound profile. You don’t need to worry about overt brightness or harsh tones, as the treble is pretty much as smooth as can be. What’s impressive, is its smoothness doesn’t sacrifice any mid-treble coloration, resulting in better height and possible details.


I was looking forward to seeing what enhancements Astell & Kern were going to make with their new true wireless earbuds, and thankfully all of them were successful. With one balanced armature, the UW100MKII is able to deliver a great sound, with more details and transparency than most true wireless earbuds are capable of. The ANC is also improved, and the physical earbuds are as comfortable as ever. Some of the controls don’t have the best responsivness, but they’re easy to work around. The UW100MKII is a complete package for those looking for a pair of true wireless earbuds with an emphasis on high-quality sound.

Pros  Cons
  • Wide soundstage
  • Accurate imaging 
  • Dynamic bass
  • Transparent mids 
  • Smooth highs
  • Comfortable fit
  • Good ANC
  • Great battery life 
  • Some touch controls are not very responsive

The Astell & Kern UW100MKII is available at Audio46.

Compare the ranking of various headphones, earbuds and in-ear monitors using our tools.

Discuss this, and much more, over on our forum.

MAJORHIFI may receive commissions from retail offers.
Previous articleEnleum HPA-23RM Review
Next articleiFi’s New Neo IDSD 2 Will Be The First Ever Lossless Bluetooth DAC/Amp
Alex S. is a sound designer and voice-over artist who has worked in film, commercials, and podcasts. He loves horror movies and emo music.