100+ Head-Fier
Pros: price to performance (value), great battery life, versatile and convenient.
Cons: design choice, microphonics, hisses when paired with sensitive IEMs and some audible hisses with KS2.
S1 | Overall: 3.5/5 Stars

More Reviews at : www.perrivanaudio.com

Price: 29 SGD


Disclaimer: I received the KB EAR S1 from **** free of charge in exchange for an honest review. My thoughts here are all my own and are in no way being influenced by them.

This is a review of the KB EAR S1, a budget Bluetooth IEM cable developed by KB EAR that minimises the need for full wired connection especially with the on-going trend with mobile devices going wireless. So, without further ado, lets move on to the specs of the KB EAR S1.


Bluetooth 5.0 wireless cable
Weight: 14g+3g
Cable length: 95cm+3cm
Bluetooth: V5.0
Plug type: MMCX/2PIN/TFZ
Battery capacity: 120mAh
Running time: 10+ hours
Charging time: about 1 hour
Qualcomm QCC3034 chip
Bluetooth 5.0+ APTX-HD technology
IPX5 waterproof certification

Build, Accessories and Design


Let’s get the packaging out of the way first since it seems to be really basic. The unit comes in a white square box and in it, the cable itself as well as a micro USB cable that you use to charge it. Not much to harp on as they covered the 2 most important areas which I care about so all is good.


Moving on to the design and build, the S1 is worn over-ear and it is designed to have a wire running behind and over your neck with the Bluetooth module hanging right below your ear which I do find it annoying sometimes as it feels as if there is something dangling around your ear as you move (MICROPHONICS!!!!!). Personally when it comes to the design, I would still prefer minimal wire runs which may or may not over complicate the product but I couldn’t find much fault with the overall comfort with the KS1 other than the stiff ear guides that runs around my ear but I think it will loosen up as I wear it more often so no major issues here.

In general, I do appreciate the overall package and design of the product despite its quirks. But, I have yet to test its longevity/durability when it comes to prolonged usage, wear/tear and other use cases so I am unable to testify these points in this review.

Functionality and Performance

The S1 I owned was terminated 2 pin-recessed which goes hand in hand with the KS2 by KB EAR. I managed to test its advertised play time and I managed to get around 9 hours ++ before the battery flats out. Pretty close to its advertised specs and of course do expect some variation given that some IEMs require more power etc. I like to point out that although simple, it was well thought out and brought a lot of convenience when it comes to pairing and button controls which I am glad as they nailed that perfectly. Connection range was good as well, I was able to move around my house without any obvious disruption in connection strength.

Moving to sound, I do notice some hiss on my relatively sensitive IEMs such as the TSMR 3 when no music is playing but not so obvious on the KS2 (still audible) which may or may not be applicable to you but just to point out that you might experience some hiss if you intend to pair it with a relatively sensitive set of IEMs. On the bright side of things, I am happy to report that it didn’t have much colouration in my subjective AB testing with the KS2 which has the potential to pair it with most IEMs without changing what you like about them besides the sensitivity issue as I mentioned above.



Now, the verdict. The S1 exceeded my expectations with its connectivity capabilities, non-colouration trait as well as its simple and straight forward implementation. Although its physical design leaves more to be desired, you get a pretty good trade off with the S1 for the element of convenience and functionality. Yes, it lacks LDAC and you only get aptX HD but from a subjective point a view, the quality of the source files dominates when it comes to listening experience. In overall, I am happy to give this product a thumbs up as it is something that provides real value to its intended audience.