First two weeks with this IEM flew by because I was too busy relistening to my music collection. It might be a little forward with the high mids and above but it is well-balanced with the massive bass and sub-bass response typical of any IEM tuned to HBB's excellent and exceeding standards. Despite its price and how it's notably bassy and punchy, it's not the bad kind of bassy and punchy; if the bass isn't there in the song, this IEM isn't going to put it in. But if the bass is in there, it's going to be very easy to hear, especially in the heavy metal albums that I listen to, where the bass tends to sit lower in the mix and the bass drums and toms tend to be more attack than body. It's also fairly reasonable on the sensitivity; I consider a volume setting of 30 or 35 on low gain mode from a FiiO BTR5 to be appropriate, and even then I put the volume on my phone to maximum very rarely, if at all.
I won't comment authoritatively on the fit because everyone's ears are different and my experience is only applicable to myself, but the small tips did not seal properly when lying down, and the medium tips would push themselves out through natural movement, so it's worth trying to find third-party tips to find that perfect fit.
Cables are also excellent. They slide past my bag's straps easily, and they don't transfer any annoying rubbing noises against my hair or my clothes. If the sockets fit, you would be well off taking the cables to use with other IEMs.
Which brings me to why I'd recommend scavenging this item's package for parts: mine is already failing after two weeks of use. The right side is already much softer than the left side, with major attenuation in the mids and highs, with somewhat less in the bass and sub-bass. This can be mitigated adjusting the left-right balance on my source to compensate, but this requires constant adjustment in order to maintain the loudness balance, and the frequency response between the left and right sides is already mismatched. There are many reasons this could happen, like metallic corrosion in the nozzle or anything to do with the wiring, but the shell cannot be easily opened for the end-user to perform any kind of servicing. And with Linsoul leaving me with no response after almost three weeks after my initial customer service request regarding my unit's failure, I can only conclude that after two weeks of use this IEM becomes either deliberately-manufactured e-waste or a deliberately-manufactured scam.
Good headphones Stay Good. This one does not.
ABCDEFGSWIS0129
