What I'd think are the most key aspects: pitch, rhythm, tonal relationships (between simultaneous sounds), progression of lines, dynamics, etc. are almost entirely not affected by audio system fidelity. Problems with fidelity are mostly manifested by uneven or otherwise shifted tonal balance and then maybe the timbre of sounds and low details (noise floor, distortion products) around the edges, so to speak. Not that those aren't important either, but are those the main focus?
That said, as far as I can tell, audiophiles have repurposed some terms like rhythm and dynamics. Either that, or... actually, I don't even know what people are talking about sometimes.
But I'm not going to fault somebody for wanting to improve the sound they get. If you don't have to be distracted by something sounding off, then good. I personally wouldn't recommend hunting for things to be upset over, but that's just me.
Edited by mikeaj - 6/24/13 at 12:40pm