what system musicians prefer? Do they care?

This discussion has gone down a few roads; as a (working! still!!) professional musician [AFM local member, orchestral musician, free lance, handful of recordings and commercial stuff, aka-the studio isn't unfamiliar] I'm also an audiophile with a dedicated music room hosting JRDG electronics, VPI TT, Maggie 3.7i and Tannoy Monitor Gold's. It's true:  musicians (and I'll lump them all together: rock, jazz, classical) don't universally have great-to-fantastic playback systems. I do; I know musicans that do. However if you look at the percentage of fine playback systems present in (lets use the orchestra I play in, or one like it as an example) the percentage probably is similar to "the general public that likes music" and how many of them have decent playback rigs. I think the comments above regarding musicians and what we listen for, and 'content vs fidelity' is spot on - so I won't bother to write any more on it. Well said. I will add a critique: musicians NEED to listen more and I"m continutally amazed at how many don't listen either to the classic recordings or keep up with what's new. I'll go one step farther-if it's listening through some speaker on their cell phone or cruddy earbuds they are not getting 100% out of the exercise. I find my professional colleagues, especially more experienced ones, stop listening and exploring at some point. I can tell the ones that haven't - and they are better off for it! In music school we all take ear training (that's how to identify chords, intervals, what is in tune, a healthy dose of sight singing too); there are plenty of classes which encourage listening to recordings, but it needs to be taught (and isn't usually) how to listen for content, performance AND fidelity. We spend hours and $$$$ trying to get the best sound possible from our instruments of choice, live, yet for many of us the "recording" is what remains as testament to what we did. In the last CD which I was part of, I was fascinated by the custom-modded Neumann tube mics (in a Decca-tree arrangement). The recording engineer/producer had some wonderful stories about that rig. Likewise the final product was great. I think I was the only person to take an interest in the tube-drivers and mics, but most members appreciated the sound quality of the final product (further still, a few never listened to it! That's another story, and not at all uncommon.) I could write on-and-on why musicians don't listen (but should) but I gotta go practice. :) seriously. I do. I don't get to turn my rig on near as much as I'd like during the symphony season. Even when I do have a little time, sometimes my ears are just fatigued. 2020 allowed a bit more time.

Great topic.  i've always wondered just the same thing.  i've listened to some great songs/scores that were recorded / engineered poorly and came to the conclusion that the artist just doesn't care or only listens to music through his phone - like 99 percent of the world does.  I've also listened to some mediocre tunes that sound wonderful and it makes me think the artist is an audiophile and really cares about using talented musicians, engineers and production.

Ok, as a professional musician, recording artist and college music professor (jazz saxophone and I’m also a symphony clarinetist) I’ll chime in. My system is always evolving but atm it consists of:

Harbeth C7es3’s 
Croft Phono Integrated
Lumin T2
Technics SL1200m3d

my start in the hobby came in my junior year of music school at U of Miami. I started going in some of the Sound Advice stores that were still around in Florida in the 90’s and ventured into the more expensive rooms where I found B&W, Krell, Conrad Johnson and Apogee. I was immediately smitten, most notably with the combo of CJ and Apogee speakers. I remember bringing in some Keith Jarrett to play on that system and my tiny brain 🧠 was blown. From there I started to save some of my gig money to buy my first good system from Sound Advice which was Kef Ref 102/2 and all Adcom Separates. Served me well for many years.
i have found that a lot of musician friends have only heard high quality playback in a studio, at least until I invite them over and then usually they are hooked. I’ve converted a number of
jazz and classical musicians into audiophiles lol. There are exceptions of course. I think one would be music professors who usually have more resources and time for this hobby, and some of the more successful musicians in my field. When John Faddis came to be a guest artist at our music school a few years ago, he came over my house for a listening session as he wanted to hear my Tektons. He has some older top end B&W speakers and he also talked about Ron Carter’s system which is relatively high end but Faddis didn’t love the sound of it. I also have a few other accomplished musician friends who are audiophiles. I think once the audio bug bites us, sometimes we get pretty deep into it as we really value the realistic timbre of live instruments. 

gano  Do those Mick Fleetwood speakers adequately reproduce the horribly nasal sounds from Stevie Nicks' voice?

I know Herbie Hancock and Keith Richards love Tetra speakers.
I landed on a used pair myself that I could afford.