Hmm....I am not sure I agree with that. I have an HTC One M7 and the Sony F886 (which sounds near identical to the ZX1). Of course to compare you must strip the sound back to its pure basics....without any kind of clear audio, or beats audio enhancements. I am using both with the AKG K3003i earphones which admittedly are in high-end territory for IEMs but they are very revealing of the differences. The M7 sounds like it is lacking in dynamics and compared to the F886 it sounds like a thin layer of cloth has been placed over the sound resulting in some of the detail being lost as well. This is not a subtle difference but a fairly considerable one. I am not for one second saying the M7 sounds bad, but with a revealing IEM, it is simply not at the same level as the Sony. I also have a Galaxy Note 3 and that has quite a similar sound do the M7 but at least in European versions has a severely crippled volume level which often has me maxing out the volume level!
But i wondered, how close did 887's SQ go, comparing it with zx1?