Kerouac
Headphoneus Supremus
amp and source definitely change the sound of the Z7 which may explain why so many varying reports. I recently got a Pono and am now listening to the Z7 in balanced mode and they sound leaner and more articulate than out of my other sources and amps.
I also think the sq out of the Z7 depends highly from the source that you use it with. With almost all my gear (the excellent Chord Hugo included) the Z7 doesn't really impress me, it just sounds OK to my ears...nothing special. But balanced out of the Pono player it scales up in an unbelievable way. If I didn't have the Pono, I probably would have sold the Z7 already...