I must be missing something with those headphone amps.
I simply plug my headphones to PC audio and listen that way. Why would I need amp for it?
Apologies for silly question, but I'm not into audio that much. Once I found my favourite headphones (Sony MDR-1A) and speakers (Ruark Audio MR1 Mark II), I did nto go back to that.
I have enough GAS from photography equipment