Question: What accounts more for the hiss with the SRH1540 and Vali; the impedance or the efficiency?  Why don't the HE-400s hiss on the Vali?   Scenario: The HiFiMan and Senns plug in to the Vali and I get no hiss (noise floor?).  Plugging the Shures in and I hear a very audible hissing.  No...

Greetings,   The headphone bug bit last spring/summer and coming up on a year later I feel like adding to the family.  I would like to expand the audio experiences available to me at home, but without doubling up on what I'm already getting.   Currently I own: -HiFiMan HE400 -Sennheiser...