This will be an extremely brief review. I had these headphones for about 4 days. The timing was not optimal for me; I was about to head out on vacation when these arrived. The question was whether I should request an few days of extended listening or just send these alone to the next reviewer. I opted for speeding the review process along.
Testing apparatus: I used a FIIO X3 Gen II for most of the listening, and then a X3 Gen I to see what happened when I used hardware tone controls to tame the bass and treble. I played rock and traditional jazz (Mingus, Miles Davis) on the units.
These headphones are great if you want a "V-Shaped" sound profile from your IEM units. That would mean a very strong, almost boomy bass and a very powerful high end response.
I would have preferred that T-Peos make some kind of changeable filters available. I did not care for the V-sound signature. The bass was simply too much for me.
A benefit of a bass heavy design is that the ear pieces do not have to be jammed into one's ear to get good bass response. Even though the headphones are fairly large, I found them surprisingly comfortable to wear.
I also found the high end signature too strong on more than 40% of the audio selections I chose.
I did try using the hardware EQ on the first generation FIIO X3. With both bass and treble turned down, I enjoyed these units somewhat more. However, my primary player (FIIO X3 Gen II) does not have hardware Q and the software based EQ is not functional on hi res files. So while adjusting tone controls was helpful, in my case that can only work a small portion of the time.
I think some people enjoy a V-shaped sound signature and they should consider these units. I would look carefully at what other headphones are used by those who write positive reviews of these units.
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I suspect those will also be V-Shared in the sound profile.
Build quality seemed good. The cable had some microphonics; but that is relatively common to all IEM units so I would not hold that against these.
In short, by design, these headphone are not designed for my listening tastes. They may appeal to others. I think T-Peos should often replaceable tunable filters. I would use the "boring old person" if it was available for these. With all that bass on tap, a neutral sound signature could be interesting.