Sticking to head-fi, I find that the four biggest factors affecting the 'quality' of the sound and music I perceive are (a) the musical content, (b) the recording quality, (c) the headphones, and (d) me (mood, emotions, fatigue, time of day, how much I'm paying attention to the sound or music, state of health, etc.). I'm not sure how I'd even rank the influence of each of these four. When all four line up in synergy, I experience bliss that can't be put into words and makes my heart pitter patter. When one or more of the four is way 'off', I can find myself neither enjoying the sound nor music.
A few posts made what I think are important distinctions about the way we're listening, i.e. our attention. I often listen to music as background music, but sometimes I'm focused on the music. If I'm listening as background, sometimes the music grabs me and either need to focus on it or I'll find myself distracted from whatever else I was doing. If I'm trying to focus on the music, sometimes my mind will wander and I hardly perceive sound or music consciously, though it would be interesting to know how the sound and music could be affecting me subconsciously without my being aware of it.
I think there's also a distinction between listening to sound versus music. If I'm listening critically and analytically to sound, like a stereotypical audiophile, that can inhibit my listening to and experiencing the music. If I try to just listen to the music and find flow with it, I find that I'm much less prone to finding flaws in the sound quality, and the perceived sound quality improves as a result. It's tricky -- I'm not really able to give full attention to both sound quality and music at the same time.
