Tronsmart Onyx Free review (with UV Sterilization)

Coronavirus outbreak, which turned into a global pandemic, made issue of personal hygiene extremely important for people. Therefore, gadget manufacturers are trying to develop new devices that meet this need. One of the first such gadget is Tronsmart Onyx Free – its True Wireless earphones have a special antibacterial charging case with UV Sterilization. According to the developers, all users needs to do is put the earphones inside the case, and procedure for sterilizing them with UV rays will automatically start.

Design, Features, Packaging

Onyx Free delivered in standard package for most Tronsmart earbuds, with the same usual kit. Package includes: Onyx Free Earbuds with UV sterilization case, short USB/Type-C charging cable, user manual, warranty card and 3 pairs eartip different size.

Design is simple and concise, which has already become familiar, almost completely repeats Onyx Neo except for some visual lines on the front. It should be noted that we consider them very comfortable and ergonomic. Tronsmart Onyx Free is made of matte plastic and given its low price, we were pleased to see that plastic is not glossy. Build quality is at a good level and when compared with previous models, build will be slightly better.

External part of earphones has LED indicator and a physical control button. Earbuds is equipped with button switches Panasonic tactile, providing convenient and precise control. Button itself has a pretty nice control that adequately and accurately performs all the tasks. On the inside there are contacts for charging and designation of earphone channel – left or right.

Charging box is made of same plastic as earphones – it is matte black plastic. It lies well in the hand and can easily be put in your jeans pocket. The lid received a magnetic connection and on the front part there are four indicators that indicate charge level of the case. On the back of box is a Type-C port.

Tronsmart Onyx Free has IPX7 protection. Therefore, do not worry about rain and etc., because these earbuds can even be submerged to a depth of up to one meter, and they will continue to work. It should also be noted that they can be used both at the same time, or separately, one at a time. The device supports working with Google Assistant or Siri virtual assistant, which is activated by pressing a special button.

Onyx Free works with an audio chip from Qualcomm. It is responsible for stable connection of earphones with combined device, high audio transmission speed with minimal delay, and low power consumption. The new product also supports aptX audio format. Onyx Free work for up to 7 hours on a single charge, and together with charging case, working time is 35 hours. Very decent performance that will satisfy almost any most demanding user.

New Tronsmart Onyx Free is designed to give you the best connection capabilities, thanks to their Bluetooth v5.0, latest standard of one of the most powerful technologies you will find. Designed for long-distance, it offers you best sound at a distance of up to 15 meters. It is a very easy model to connect. And thanks to this, this model has other improvements, such as being able to connect your smartphone quickly and stop music when you take off earbuds without any problem.

UV Sterilization

At the bottom of case you can see two LEDs, they are responsible for UV sterilization. Sterilization is activated automatically every time you put earbuds in the case. You cannot disable it or manage it in any way. If you do not close the case to the end and leave a small gap, you can see purple glow for about one second. This is all how you can interact with this function.


Sound quality of Tronsmart Onyx Free is as good as that of previous models. It uses the same 6 mm dynamic driver, which sounds pretty dynamic and voluminous. At low frequencies, you can hear a pleasant bass, which is accompanied by warm and surround sound. Medium and high frequencies are set correctly, even at the maximum volume level. In general, this is the same well-known and nice sound in this price range as in the previous Onyx Neo and Spunky Beat models (thanks aptX codec).


We can’t say how much UV sterilization is really useful and what real effect it gives, but considering price, their really good sound, along with excellent working time and nice specifications (aptX, Bluetooth 5.0, IPX7 protection), Tronsmart still offers one of the best offers in this price segment.


Model: Onyx Free
Chip: Qualcomm QCC3020
Technology: Qualcomm aptX audio technology, cVc 8.0 noise cancellation technology, DSP
Bluetooth version: 5.0
Audio code: aptX, AAC, SBC
Bluetooth profile: HFP/HSP/AVRCP/A2DP
Driver: 6mm
Transmission distance: Up to 15m/50ft (open area)
Microphone sensitivity: -42dB ± 1dB
Impedence: 16Ω
Playtime: Up to 7 hours (50% volume): up to 4 hours (100% volume)
With the charging case: Up to 35 hours(50% volume)
Battery: Earphones: 40 mAh; Charging case: 500 mAh
Charging time: Earphones: 1 hours
Charging case: 2.5 hours
Charging port: Type-C

Official site:

Buy: on Aliexpress official store.