And the biggest influence on sound quality is...


The quality of the recording itself.

Then the room, the setup, the speakers, and lastly the  front end.

I've got recordings that make my system sound horrible, and I've got recordings that make my system sound absolutely wonderful.

None of the gear changes have had that much impact on sound quality.

 

 

tomcarr

Room 1st which includes dimensions and treatments.

system synergy 2nd - from cables to matching amp to speakers.

3rd is speakers sized for the room. You don’t want small monitors in a 30’ room and you don’t want large Wilson’s in a 10x10’ room. I had large speakers in a dedicated room within a room 27’ long with 15’ ceilings. I moved to a smaller house and tried the same speakers in a 16’’ long room with 8’ ceilings, great speakers in a large room to terrible sounding in a much smaller room. 
 

Right behind the speakers are the amps/dac/preamp all spec’d according to the value of the speakers. Your not going to spend $2000 on an amp if you have $100,000 speakers and you wouldn’t be spending $100,000 on an amp and dac if your speakers cost $3500.

Ultimately, recording quality and room will define the limits, but I am talking about top level equipment. In your average $50k system I am not sure which component contributes most. But I belong more to source first school, so, I guess, it's either the recording or "transport", be it turntable itself, cd transport or tape deck transport. Poor recording will sound like junk anywhere but with average recording the better your set up is the better it will sound. It's a continuum from very poor to great recordings, and I think the answer to the question is more complicated than this or that.

The room and the system are what they are, recording quality easily the greatest variable. Now, one  can manipulate and change audio components and room treatments, same doesn't hold true for any particular recording.

This is a fun thought experiment.

If your source is LP, then I would argue that your playback system (turntable, arm, cartridge, setup) is most important.  Imagine you had near mint pressing of Kind of Blue or Aja, and you played it on a $35 Crossley.  It would sound like sh*t.  However, given a decent playback system, the recording is next.

Digital is very different as you can get acceptable sound from a modest or inexpensive source.  Here I would put the recording quality first.

Then it gets difficult.  Speakers are very important but require a suitable amplifier and proper setup in a room that they work well in.  Too many dependencies, but if I had to rank: Speakers > Set-Up > Room > Amplification.  Then comes the fun of cables, power, and tweaks.