I disagree with you about the fact that sound should depend on the instrument. It's like my teacher says: "You don't have to buy an expensive instrument when you can't get a good sound out of an intermediate one."
I can say that last year my tone on my clarinet was as average as most clarinet student in my school. But this year I learned a lot about listening to myself and trying till you get the right sound. I only played two pieces during clarinet lessons this year, but my sound quality improved more than over the last 9 years I'd been playing.
So not only technique, but also working on tone quality makes a great musician.
ok, that's true but I meant that many people can learn how to sound good. As is the case with flute: the rule there is to open up, and it's no big deal.
what is that extra that only the select few have? On top of tone etc.
I believe it takes passion.
No passion no music.
Too many musicians are really dead on the inside, and that is what saddens (is that a word??) me the most.