And the biggest influence on sound quality is...

Back in the early 80s I sold, delivered and set up a system for a customer who was an opera nut, was well off financially, and was beginning to realize his mortality…he had an illness soon to be known as AIDS.  He lived in a brownstone on Commonwealth Ave. in Boston’s Back Bay…a very exclusive location.  I sold him a pair of KEF 104/2s, a NAD 7155 receiver, and matching CD player…good gear, but not what we call High End today, or then.  The room was amazing…high coffered ceilings, oriental rugs, dark wood library shelving, a baby grand Steinway.  I wired it up with 16 ga. zip cord off a spool, as we had no advance notice what lengths would be needed.  The sound I heard from that system was better than anything I had imagined possible.  It was the room.

If you're just getting started, the speakers and room are the places to spend your resources, but at some point it all matters.  Once the system reaches a higher level, you need to more careful to match anything new that gets added to the system level or it'll become the weak link....and the weak link is usually matters most.  

...a glass of great wine.

Quality of the recording because it sets the ceiling. You can reach it or you might fall short of it, but you can’t exceed it