TRN BT20S Pro Review

TRN BT20S Pro Earpieces

True Wireless Earphones (TWS) has seen an increase in popularity in recent years. Their main appeal is their functionality. Simply take them out of their case, and they instantly pair with your smartphone. 

And when you are done using them, just put them back in their case and they will instantly disconnect and recharge their internal battery. There are no wires connecting each earbud, which makes them very convenient tools for your workout sessions or commute. 

However, TWS earbuds have one major criticism from enthusiasts. They simply fall short when compared to IEMs when it comes to the sound quality. Sure, there are great sounding pairs like the Sennheiser Momentum True Wireless 2, Sony WF1000XM3, Lypertek Tevi, and Apple AirPods Pro

But at the end of the day, those earbuds still won’t match the raw performance of audiophile IEMs. But brands do acknowledge this and are always finding ways to improve the wireless experience. 

One company that is looking to innovate the TWS is TRN. With the release of the BT20S Pro, they are looking to turn your wired IEMs into true wireless earbuds. We have seen this concept from other companies before. But unlike its predecessors, the BT20S Pro now includes a charging case that mimics TWS charging cases. 

The concept is very good in theory. But can the BT20S Pro truly deliver on its promises? Keep on scrolling to find out. 


The review unit was provided by TRN Audio. We would like to thank them for their support and for making this review possible. However, this does not influence our review in any way. Everything written here is my honest opinion.  


Packaging and Accessories

bt20s pro packaging and accessories

The BT20S Pro has a relatively simple packaging. You get a small box with a photo of the product at the front and the product specs at the back. The design is very similar to the TRN V90s, which we will also be reviewing. 

The only accessories included in the packaging are the USB Type-C cable and the instruction manual. The charging cable is pretty basic and doesn’t have the best quality. You will most likely replace it with your smartphone charger. 

The instruction manual contains information on how to set up the device. However, there are some things missing, which we will be discussing later. 

Design and Build Quality 

Charging Case 

One unique aspect of the TRN BT20S Pro is the charging case. Most of the older generation Bluetooth cables had no charging case and needed to be charged separately. But with the BT20S Pro’s charging case, you get an experience that is a lot closer to the TWS earbuds. 

Its design, however, leaves some things to be desired. I am not a fan of the materials used as it resembles the generic cases that usually come with most Chi-Fi IEMs. It doesn’t stand out and can easily be mistaken as a regular earphone case. 

It is also significantly larger than the charging case of most TWS earbuds, which makes it harder to carry around. You’ll likely need a bag to carry these. Most TWS earbuds such as the Lypertek Tevi and Apple AirPods Pro can easily fit inside your pocket.  

bt20s pro charging case inner

One significant issue that I had was the fitting of some IEMs. I had trouble fitting some of my larger IEMs inside the case. This is because there are no grooves inside to accommodate IEM shells. 

The compartment found on the upper part of the case designed to store ear tips and cables makes the fitting issue worse. None of my IEMs would fit inside the case if I decided to use that compartment. But once it is empty, the fitting of most of my IEMs, such as the KBear Diamond and BQEYZ Spring 2, didn’t have issues. 

In terms of the build quality, the charging case felt solid and sturdy enough to protect the IEMs inside. The charging pins worked well, and I didn’t have to reposition the earpieces whenever I put it back inside the case. But take note that the position of the left and right charging pins are reversed, so you’ll have to get used to that orientation whenever you put back the earpieces. 


bt20s pro adapters

The design of the earpieces is very similar to most of the offerings on the market. The earpieces feel similar to the ear hooks found on IEM cables, with the receiver being located at the back of your ears. This is a tried and tested design, so I have no complaints here. 

The BT20S Pro is made of plastic and has lights to indicate whether they are paired, disconnected, or charging. They are also very lightweight and won’t cause any comfort issues. 

But unlike its competitors, the earpieces feature a modular design that allows you to swap the stock module to different IEM sockets. This is a neat feature to have since you don’t have to buy another unit just to accommodate IEMs with different socket types. 

Removing the modules is pretty easy. But once you attach them, they are pretty tight and secure, so they won’t just fall off by accident.  


The BT20S Pro has one button on each side. It is located at the back, which I prefer over TWS earbuds since you don’t have to press the shells against your skull. They don’t feel too tactile, but they aren’t too mushy either. 

The buttons mainly control the playback controls as well as the power on/off of the earpieces. There are, unfortunately, no volume controls. 

One minor complaint that I have with the buttons is that both the right and left buttons have the same function. This wouldn’t normally be an issue but I think it would have been better if the next track and previous track were to be placed on each earpiece. This would have also theoretically added more room for volume control. Unfortunately, there is no option to remap the controls. 

Pairing Process 

bt20s pro pairing with fiio m11

Unfortunately, one of the more challenging aspects of the BT20S Pro was the pairing process. Most consumers would assume that you simply have to take these out of the case and pair with your phone, just like with any TWS earbuds. However, this was not the case. 

If you try pairing them with this method, only one of the earpieces will work. You have to do some additional steps to sync the two earpieces together before connecting to your phone. This was not mentioned in the BT20S Pro’s manual and I had no idea how to fix this. 

Luckily, the pairing process was similar to the older TRN BT20S. So I jumped into Reddit and checked how the BT20S was paired. This was a bit inconvenient and I imagine users who are not very tech-savvy might not know how to fix this problem. I suggest TRN include instructions on the pairing process on future releases. 

Or it would even be better if both earpieces were already synced out of the box. After successfully pairing the BT20S Pro with my device, I had no more issues. You do not have to sync the two earpieces again if you want to connect the BT20S Pro to a different device. 

Wireless Codecs

bt20s pro verdict

The BT20S Pro supports various codecs. But the main highlight is the APTX support, which makes sure that you are getting high-quality audio. It would have been nice to see other codecs such as LDAC for phones that don’t support APTX, such as Huawei smartphones. But for most users, the available wireless codecs should be good enough. 

Wireless Performance and Sound Quality 

trn bt20s pro with fiio m11

The one that will make or break the BT20S Pro, is, of course, the wireless performance. And surprisingly, the BT20S Pro performs as good as my Lypertek Tevi TWS Earbuds. 

The connection remained stable even if my smartphone/DAP wasn’t close to me. I tried going around our house while leaving my source on the first floor and I did not encounter any issues. Using each earpiece independently is also possible just like in TWS earbuds. 

There were also no interruptions while using the BT20S Pro outside in more packed areas. I did encounter interruptions in areas with strong interference. However, this has happened to all of my TWS earbuds so this is pretty normal. 

I will, however, warn our readers that several users have been experiencing disconnection issues with the BT20S Pro. I have not experienced this issue on my unit. Make sure to purchase the BT20S Pro in a reliable shop where you can return/replace them if you ever get a bad unit. 

In terms of the sound quality, there were virtually no noticeable sound degradations with the BT20S Pro. I used the BT20S Pro on my entry-level to mid-end gears (KBear Diamond, BQEYZ Spring 1, BQEYZ Spring 2) and they all performed as good as they are on wired mode. 

The volume was, however, not as loud as I would like. I was almost maxing out my smartphone’s volume. The experience with more demanding IEMs and more sensitive IEMs may not be as good with the BT20S Pro. 

In terms of the microphone quality, the BT20S Pro performed pretty well. Callers on the other end did not have a problem understanding me, even in busy environments. However, the quality is still not as crystal clear as dedicated TWS earbuds such as the Lypertek Tevi or the Apple AirPods Pro. 

Battery Life 

You don’t normally expect these adapters to have exceptional battery life. However, the BT20S Pro has exceeded my expectations. The earpieces are rated to last for up to 9 hours while the charging case is rated up to 72 hours. That is as good as my daily driver earbuds, the Lypertek Tevi.

To put these numbers into perspective, I have never fully consumed the 9 hours on each earpiece. It is more than enough for short listening sessions and even long listening sessions when I’m listening to one or two full-length albums. 

And when you throw the charging case’s 72-hour battery in the mix, you’ll likely use the BT20S pro for up to one month without needing to recharge. 


The BT20S Pro is not a perfect product. However, it successfully brings the TWS experience without compromising on the sound quality. I highly recommend the BT20S Pro but only if you can get some sort of warranty or testing period to make sure that these do not have any of the disconnection issues that some users are reporting. 

The TRN BT20S Pro can be purchased at TRN’s Aliexpress Store as well as on Amazon


  • Standby time(Bluetooth modules+ charging case) :180H+720H
  • Playback time (Bluetooth modules + charging case) :9H+64H
  • Transmission range:10m
  • Bluetooth version:5.0
  • Charging current :DC5V,1A
  • Charging time (modules/charging case):1.5H/ 2.5-3H
  • Modular power capacity:80mAh
  • Charging case power capacity:700mAh

Albums Used For Testing 

  • Milet – Eyes 
  • Babymetal – Metal Galaxy World Tour in Japan
  • Babymetal – Metal Galaxy
  • Mamamoo – Reality in Black 
  • Nobuo Uematsu – Distant Worlds: Music From Final Fantasy 
  • Pentatonix – Pentatonix Volume 2 
  • Lindsey Stirling – Artemis 
  • Moe Shop – Moe Moe

Devices Used For Testing 

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.