This one of the greatest sax players that ever lived. His music is a bit full on for some..  But look how high he holds the sax.  He pushes it up  against his top teeth, and pushes his chin down to his chest to keep his bottom jaw relaxed and his teeth away from the bottom reed.. This is how to get a great sound and to avoid squeeking and harsh notes… many people do the opposite of this and then wonder why they can’t play softly or control their sound

Coltrane starts playing about 3 minutes in.. but you may want to watch it all to see the ever cool and  tasteful Miles Davis…