great musician's audio systems

Paul from Dave Letterman has Andras. I think the II's and Pass amp. Don't think he put much thought into it. Heard the system, it sounded good so he bought it.
Some people get lucky the first time around.

Tvad

Worked out OK for Arnie Freytag

I think he had a bigger lens than me.

When employed at Wilson Audio in 1996, I had the pleasure of working with Lenny Kravitz on several occassion because he kept damaging tweeters in his WATT/Puppies. I believe he was using a Krell FPB-300 to drive them.

For years Lee Landesberg (of Landes Audio in Chester, NJ) claimed that Keith Jarret used his (Lee's) speaker designs. Lee no longer designs, builds his own speakers so I'm not sure what he uses.

Musicians don't need fancy equipment, though there are many stories like Patty labelle and VR9s et al. The reason they need little in terms of fancy stuff is that musicians hear a piece of music in their head and the recording is just a cue.
My wife played violin very seriuosly as a child protoge, in music camp, then college and beyond but she has given it up for many years now.
I went to buy my first high end system and was shopping for weeks. My wife just couldn't get it. She is definitely not tone deaf or has ruined her ears with loud music. She said what is the difference they all sound OK just buy one already. I had made inumerable changes to that system which she took ownership of and the changes didn't matter in the least to her. The music is in her head.