This is a deep topic. Very interesting to think about. It starts in your mind, how you touch the guitar with your hands and how the guitar interprets that through your rig, and how your rig in turn interprets that, then the speaker, the mic, the console, etc. It's crazy complex, man.
Brilliantly stated! I've often said its a hands>ear>brain>hands (etc) feedback loop.
When in graduate school, I was playing a lot of acoustic guitar inspired by the Al Di Meola, John McLaughlin and Paco De Lucia trio. Check out their recordings if you've never heard them, OMG. Pure mastery. Of course, I couldn't play the way they did, but the dynamics and vocality of their playing entirely changed how I approached mine. Their guitar tones are insanely good, and that acoustic input is where it all starts. It made me learn to use less compression in my electric playing so I could hear the transients more, and try to allow my own playing dynamics to come through and sparkle. It also made me learn to use heavier strings and play with less force.
Dynamics are so important in music. Of course if you love the above players, you know Return to Forever, with the greats DiMeola, Stanley Clarke, Chick Core (RIP) and Lenny White. It was inspiring to listen to. I loved DiMeola's 'Elegant Gypsy' album after RTF, too, and listened to it over and over, and got into the Chick Corea recordings as things in his career progressed. My playing, whether keys or guitar is a million miles beneath their stratospheric heights, but they've been inspirations. Same with McLaughlin (remember when he took Santana under his wing?) and Paco De Lucia. Greats.
Then there are Pat Metheney and Lyle Mays...also fantastic creators and players.
Ultimately though, your question is where your concept of tone comes from. Maybe its an evolution of what you are hearing, what you've heard in the past and how that touches you emotionally. Great tone blesses people, man, it just does. I was talking with the great Steve Miller long ago about how mp3 and other compressed music technology has brainwashed humanity out of the medicinal effects of high quality sound. No one hears what those guys heard at the mix desk, which was intended for everyone to hear. I met Andy Johns at Steve's home studio when they were mixing Steve's blues album around 2009. I watched them tailor the mix through $60,000 (each!) studio monitors, it was f8cking crazy, man. Andy would nudge the fader and tweak the guitar for "more balls", finesse the reverb on the drums, all that. It sounded so good. Pressed down to vinyl and played in a nice room, you'd have a chance. Now most of us don't do that anymore. So that concept of tone really comes from listening. The more we hear, the concept expands. That's why you play PRS, man. True? True.
What a fantastic experience that must have been!
Like you, I can't stand listening to lossy audio formats like MP3. I can barely stand listening to satellite radio in my car on trips!
In my studio, I listen to other folks' recordings through Audirvana Studio. It's a high fidelity player that sounds worlds better than Apple Music's player, and you can set it up so it handles the audio for the entire rig, including Apple Music, which I sometimes have to use to reference client requests.
However, I don't run my recording software through it, because both Logic and Luna, the DAWs I use, have great fidelity.
Apple Music will play AAC, which isn't a very lossy format, instead of MP3 if you tell it to.
I've been lucky enough to work in world class rooms since the early '90s, and loved the time I've spent in them: GTN Studio A (most often there because it's nearby - it's a Russ Berger-designed studio that's easily as well done as any, anywhere); Right Track NYC, Producers Color, The Record Plant LA, Wisseloord, Netherlands, and Plus XXX Paris, etc., are other favorites. A few no longer operate, sadly.
Nonetheless, a smaller,
correctly treated room with a first class set of near field monitors comes awfully close in fidelity at the mix position - the main difference is ability to handle volume and the low frequency content.
I also love the Audeze LCD headphones that lots of mastering engineers have been using to reference their mixes; the great mastering engineer Glenn Schick uses a pair of Audeze exclusively now, and doesn't even bother with speakers. During the COVID days I used them to mix national ads with clients using real-time, HD quality AV software and hosting called Evercast, with clients on their computers remotely so they could participate.
I sent out sets of decent headphones via Fedex for clients to use for the sessions, so they could actually hear with reasonable fidelity. I've thought of mixing other folks' music doing that, but haven't gotten around to it so far - I don't know if there would be a market for it. Seems like a good idea, though.
So excellent cans are another valid choice instead of spending a fortune treating a room, and you hear everything with the best cans. They sound natural and they're accurate. I have to use Sonarworks with other headphones, but not with the Audeze.