How does sound influence your appreciation?

I think it’s true that better sound quality helps with getting into unfamiliar music and genres as has been said already.

Arguably, that’s more important than giving fresh perspectives on old favourites. Is it really that big a deal to hear parts of the mix that previously went unnoticed?

It depends on the system, to me. Many systems are oriented towards scraping and exposing the most minute details. These will present the venue and mastering and can mask the music... drawing emphasis to the system. I used to have one of these. To me this restricted my appreciation to the very finest recordings and as close to my core preferences in music.

Alternatively very musical natural systems present the venue and mastering in proportion to how they would be in real life, if you were there. In this case, the system I have now, will draw me in to all sorts of music that I would never like normally. Another major parameters that draws me in is the rhythm and pace... here music with a very good beat will really suck me in... I’m thinking of pop and some other genre I normally do not like.

@rvpiano

Perhaps my system isn’t yet good enough to afford such experiences but on the other hand, listening to familiar music that I don’t particularly care for on systems far better than mine has not changed my responses. I don’t enjoy such music any better when it’s presented in better SQ. What engages me in music are melodies, chord changes, rhythms, timbres, and all the expressive means available to skilled improvisers within the genres I enjoy. Sonics are not going to change any of the above. Better SQ may enhance my listening pleasure of what I already enjoy but so far, I haven’t found it enables me to enjoy music I haven’t previously enjoyed.This doesn’t mean I discount SQ. I try to seek out the best possible sounding cds and upgrade gear when I can. I simply don’t experience the transformative capacity you've  described.

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I like the good recordings. I really enjoy listening those. Poor recordings not so much. I tend to want to listen to the capabilities of my system.

Things are always better when the senses are fully engaged. 

I have found that as my gear improved, the SQ of well recorded/mixed/mastered source material improved and I found myself enjoying genres of music that had previously left me cold.  Jazz and classical, to be specific.  However, I also found that (for me) poorly recorded/mixed/mastered source material of any genre sound worse and I don't like it as well as I did when my system was less resolving.  A double edged sword I guess.