Hello people , I've recently bought the black ZST. Easily driven. Responds well to my fiio e5 bass boost. Very sensitive to the source. Could be a little bit better on the mids. (more @ the background instruments). A quick fix is to use more volume. Nice design (people pay attention). Very good...

I have an iphone 5 and recently bought a LG G4, so my comparison is between these two. The sound on LG g4 is far WORSE than Iphone 5.   I've returned the LG G4 to the store and kept my iphone 5.

I have  - Sennheiser HD219 -Sennheiser HD205 DJ -Sennheiser HD202 (sold) -Sennheiser HD229 (sold) -Grado SR80i -Koss PortaPro   and now, the JVC HA-S400!!!!   The cheapest by far here in Brazil and you bet? THE best among the ones I listed. Very easy to drive!   Superb separation...

There are tons of fake ie80 being sold on chinese websites..like aliexpress. I've bought one and the sound quality is MUCH worse than a stock ipod in ear phone.