Astell&Kern AK UW100MKII TWS Earphones Review: For the purists on a budget

Pros:
- Clean and detailed sound output
- Built-in 32-bit AKM DAC
- Customisation through companion app on Android and iOS both
- Support for aptX Adaptive codec
- Unique design, sturdy build
- Dual pairing support, Ambient sound mode
- Good battery backup
- Great pricing for the sound quality

Cons:
- No active noise cancellation
- Bulky earbuds and charging case
- In-ear fit is not the most reassuring
- Average call quality
- Temperamental touch controls

Price: Rs 4,999
Rating: 3.8/5

Astell&Kern may be new to many here in India, but this two decades old Korean audio brand has a strong global following. Their AK UW100MKII true wireless (TWS) earbuds aren’t exactly a recent launch. Yes, they officially reached our shores probably in the last quarter of last year, but the companion app for devices running versions of Android prior to 15 only released right at the end of 2024. But more importantly, never before were these $300 earphones selling for one fifth of that cost as they are now in India.

Irrespective of whether you view this as a massive discount or the company trying to clear their stocks by dumping them here, a sub-Rs 5,000 price tag makes the AK UW100MKII a very interesting proposition. How does it perform? How does it compare to some of its modern counterparts in terms of features? Is it worth buying at its current selling price? Let me answer all that and more.

Astell&Kern AK UW100MKII: Design and Comfort (7/10)

The earbuds sport a peculiar pentagonal design with a smooth matte finish. They look good in two shades of gray but the buds are chunky. The same goes for the charging case too, which is quite bulky and not very pocketable. The buds weigh about 7 grams each and the case tilts the scales at 65 grams, which puts them both on the heavier side. A distinct status indicator LED is located at the front of the case, while a USB-C charging port can be spotted at the back. A pairing/reset button is absent.

The buds feel comfortable in the ears but they do stick out noticeably. The fit isn’t snug enough, especially when you move around. It’s a non-issue when you are stationary or making some light movements, but I found myself adjusting them on and off on walks and jogs. Hence, despite the buds being IPX4 rated sweat resistant, I wouldn’t recommend them if you are looking for a pair to wear during a workout or a jog.  

One thing really good about these AK earbuds is the passive noise isolation. The right sized silicon tips from the handful of bundled pairs offer a very good seal and block out quite a bit of ambient noise. This is necessary as there’s no active noise cancellation (ANC) here. The touch zones are present at the back of the buds and you are supposed to tap at the vertex but the touch sensitivity is a bit moody. The good part is no accidental inputs are registered if you touch other areas at the back while adjusting the buds.

Astell&Kern AK UW100MKII: Features and Specifications (8.5/10)

Each earbud is fitted with a Knowles Balanced Armature driver, something incredibly rare in this segment. But as I mentioned earlier, these Astell&Kern earbuds were never meant to be a sub-5K product. You also get a built-in 32-bit AKM DAC and two microphones (in each bud) for calling and noise suppression during calls. You do not get ANC, but interestingly, there’s an Ambient mode to stay aware of your surroundings.  

Given that this isn’t a recent launch, you get a slightly older Bluetooth version (5.2) but the codec support is good with SBC, AAC and more importantly, aptX Adaptive compliance. You also get wear detection sensors and multi-point support with simultaneous pairing with two devices; both features work well. You now get the AK Control app for most Android and iOS devices to access various features of this product.  

Though the tweaks aren’t as elaborate as the companion apps from Sony, Sennheiser or even OnePlus, it does cover the basics. While it offers six audio presets and a multi-band equaliser for creating your own sound profiles, the options to configure controls are very limited. You can only assign or alter functions for double tap and triple tap gestures for either earbuds from the few available options. You can select a DAC filter and alter the ambient mode depth too in addition to updating its firmware when available.

Astell&Kern AK UW100MKII: Performance (8.5/10)

Typically, in the sub-Rs 5,000 segment of wireless earphones, one expects products with a V-shaped sound with boosted bass, if not abundant. I am happy to report that the AK UW100MKII is not one of them. It stays as close to neutral as possible with excellent mid-range reproduction and sharp highs. It isn’t bass-deficient but certainly not a product for bassheads. The lows get no preferential treatment, and that results in a wonderfully balanced sound with excellent detail.

The vocals are crisp and clear, instrument separation is very good, and the highs are sharp and well-tempered without sounding sibilant. The soundstage is reasonably broad and the overall detail in sound here is hard to find in this price bracket or even in something priced one and a half times these AK buds. Though not the loudest around, these earphones are perfectly audible around 75% volume even when outdoors, and the sound doesn’t crack if you push it to 90% either.

The AK Control app, now available for older versions of Android too along with iOS, lets you tweak the sound further. You get six audio presets, of which, Natural and Balance provide the best results, and should suffice for most. You also get an equaliser to finetune the output to your liking and create custom presets. We did not face any latency issues when watching videos, with no noticeable lag between the video and audio. The wireless range is perfectly fine with a strong connection up to 10 metres with a clear line of sight.  

This is one of the rare or unusual pairs of wireless earphones that do not have ANC but have an Ambient mode. One can adjust the amount of background noise that is being let through using the companion app; you have four levels to choose from. While it is good enough to stay aware of your surroundings, it is not the best for having a conversation with the buds in your ear. Also, while the company takes pride in the passive noise isolation here, it doesn’t hold up that well in buzzing areas or in public transport. You do miss ANC there.

Astell&Kern AK UW100MKII: Call quality (6/10)

This is probably the weakest aspect of these earbuds. The call quality here is average at best. The caller can be clearly heard but your voice feels subdued and the clarity is a few notches lower. It is still manageable indoors, but when outdoors, the person on the line had to really strain his ears to hear me clearly. So if you are looking for earbuds for frequent calling, I wouldn’t recommend this AK product.

Astell&Kern AK UW100MKII: Battery life (8/10)

The battery backup here is quite robust. The company claims 9.5 hours for the buds and 29 hours overall with the charging case. With loudness close to 75% during testing, the earbuds managed to go on for close to 8 hours on a full charge, which is impressive. The charging case could juice them up fully twice more taking the overall battery backup close to 24 hours, which is good.  

The above figures are without the use of Ambient mode. With a sporadic use of the same, expect a backup of close to 20 hours overall. Fast charging figures are quite modest, with a 10-minutes charge promising an hour of playtime. The battery level of each earbud and the charging case is visible in the companion app. However, if the app isn’t installed, you do not get to see the remaining charge on the buds or the case at all on the paired device, which is weird.  

Astell&Kern AK UW100MKII: Price, verdict, alternatives

The Astell&Kern AK UW100MKII is priced at Rs 4,999 with a one year warranty, which is a great price for its sound quality. So is this the best pair of TWS earbuds to buy under Rs 5,000 in India? Yes and no! If you truly like close to neutral sound without any boosted bass, these are easily the best sounding earphones around 5K, despite a bunch of shortcomings listed above. But again, only if You like that kind of sound and not because some self-proclaimed ‘audiophile’ influencer or friend says so.

There is no shame in preferring a little extra bass in the sound. It’s an individual choice, just like spiciness in food; nothing right or wrong about it. If that’s the case or if you need more features like ANC or better call quality or even a more comfortable fit, there are a lot of excellent options around Rs 5,000 in India that will serve you better. The OnePlus Buds 3, Nothing Ear (a) and Earfun Free Pro 3 would be our top picks. But if you are a connoisseur of detail in audio, nothing comes close to the Astell&Kern AK UW100MKII in this price band.