If you have not heard of Astell&Kern you would not be alone.  They are a subsidiary of iriver, a South Korean consumer electronics company, and their products are the premium successors to the iriver audio products.  They are known by audiophiles for their high-end headphones along with their DACs for those who want the best possible sound.

Until now, all their headphones have been wired as you would expect from an audiophile company but with the release of the new AK TWS UW100 they are moving into the true wireless market.  Their goal is to reproduce their high-end sound in a TWS product and in fact produce a “best-in-class hi-fi grade sound”.  Read on to hear if they managed to do that.

Design and features

The TWS UW100 are not small earbuds but their unique design allows them to sit comfortably in the ear, without the use of any wing or any other type of hook to secure them in.  This of course means that rigorous movement may not be kind to them, although no matter how hard I shook my head I was unable to dislodge them.

Given their history with DACs it is no surprise to see Astell&Kern include a separate and dedicated AK4332 32-bit “high-performance” DAC in the earbuds.  Unlike other manufacturers who include the DAC integrated into the Bluetooth chipset to lower power consumption the separate DAC allows for a much-improved sound quality – in theory.

Each earbud has a single touch panel with useful and easy to use actions but there are not many options for each earbud – you can change it within the app.  I settled on a simple play/pause being a single tap of the right earbud and ambient mode on and off with a single tap of the left button.  There are also functions for double and triple taps and a tap and hold action.

The earbuds do not include ANC but instead offer passive noise isolation (PNI) with their ambient mode.  Other features include aptX codec support, Bluetooth 5.2 and Knowles Balanced Armature drivers for that high quality sound. One thing they don’t have though is an official IP rating so be careful not to get them wet.

The charging case is of average size for TWS earbuds although it may take a few tries to get used to putting them in the correct way so that they charge correctly.  The charging case does support wireless charging and holds a full 18 hours of power within the case – the earbuds also offer 6 hours of playback.  Just 10 minutes of the earbuds in the charging case will provide an hour of playback thanks to the fast charging.

Comfort and fit

The earbuds fit into the ear well thanks to their pentagon shape which somehow fits my ears extremely well – they are screwed in to lodge them into place.  This makes them not amazingly comfortable, but I was still able to wear them for a good couple of hours without any issues and they did not at any time feel like they were going to fall out.

Included in the box to help with your fit are five different sized silicone ear tips.  I had to try out a few of them first before I found the one that fit my ear the best.

Sound quality

The inclusion of PNI instead of ANC results in the removal of mid and high-end ambient noise instead of the low end that ANC does.  This results in a more accurate sound according to A&K and considering the quality of the sound from these I believe them.

So is the PNI any good?  I stuck the AK UW100 into the ears, on relatively loud and had my son yell at me from less than a metre away.  I couldn’t hear him at all.  This is of course thanks to not just the PNI but also the tight fit in the ear.  The lack of ANC also helps the accuracy and quality of sound according to AK and who am I to argue with them – the results speak for themself.

The other flagship high end set of TWS earbuds I own are the Bose QC Earbuds which are outstanding on their own.  The Bose QC Earbuds offer true ANC along with a great sound but unfortunately there is no granular control of the sound using an equaliser with the app not offering that option.  It was fairly obvious that I was going to have to compare these AK UW100 to them.

Without the AK TWS app the Bose were as good as the AK UW100 but once I’d managed to find the AK TWS app on the Play Store and tailored the sound to what I was listening to at the time the difference was night and day – and I never thought this would be the case.  

Not only are the AK TWS earbuds able to reach a louder level than the Bose earbuds but the sound is deeper and richer.  The range of sounds they are able to discern just seems to be much more than the Bose.  They are crisper, louder and a nicer experience, no matter what you are listening to.  

The Bose seem to have a deeper bass but switch the AK TWS app over to the bass EQ and the bass on the AK UW100 just seems more accurate and crisper.  I can see why AK are considered an audiophile brand because the sound is damn near immaculate.


There is a first version of the AK TWS app on the Play Store and while it is a first version it still works.  The EQ settings are very basic but the five sound options give you different sound profiles and I found them really good although it would be nice to be able to have much finer granular control of the equaliser.  Maybe in the future.  Personally, I set it on Bass emphasis mode and loved the sound balance of decent bass with great mids and highs.

Future OTA updates to the earbud firmware will be provided through the app so it is definitely something you should install and use.

The only issue I had with the earbuds was pairing them with my devices, whether it be phone or laptop.  Taking the earbuds out of the case automatically put them in pairing mode but for some reason the pairing mode is not a stereo earbud set device – the phone or laptop kept seeing multiple AK options to pair but every one of them failed, and not one of them showed the headphone icon signifying the pairing of a headset.  Eventually it worked for my phone but did not for my laptop.  

I did figure out how to get it to pair successfully each and every time: by putting them into pairing mode yourself by pressing and holding on the earbud button for three seconds when both earbuds being worn.  If you get these earbuds and have trouble pairing, use this little trick – I dare say a future firmware update is something that will fix this.

Would I recommend them and where can you buy them??

The Astell&Kern UW100 are not cheap for a pair of TWS earbuds but they produce the best quality sound I have ever heard from a TWS earbud. They lack ANC so they may struggle with the engine noise on long flights (I will test them out next week and update this review accordingly) but the PNI is amazing and helps keep the quality of the sound high.

***UPDATE*** After testing both sets of earbuds side by side on the short flight to Sydney I can say that if it is music you are listening to then the AK UW100 sound better thanks to the PNI and their better sound but if you are specifically trying to listen to spoken word whether in a movie or podcast then the noise of the engine will overpower the quieter moments. In that case the ANC of the Bose made the dialogue easier to follow.

I can highly recommend the Astell&Kern UW100 TWS earbuds if your priority in a set of TWS earbuds is quality sound. The Astell&Kern UW100 (RRP AUD$399/NZD$449) will be available from late March exclusively via BusiSoft AV and its dealers.