An Introduction to Donald S. Reinhardt's Pivot System
Go halfway down that Web page to "Reinhardt's Embouchure Types"
A Type III (Roman numeral foer "3") is downstream, meaning that the lower lip curls under the upper lip so that the air is projected downward.
The trumpet is often tilted downward as the player ascends to high notes.
That player type often uses more upper lip than lower lip, so that he plays low on the mouthpiece.
Maynard Ferguson is a famous Type III player.
A Type IV (Roman nummeral for "4") is an upstream type, meaning that the upper lip curls under the lower lip so that the air is projected upward.
That player usually has a receding lower jaw while not playing, then the just thrust foward during playing.
The trumpet is often tilted up a little as the player ascends to high notes.
That player type often uses more lower lip than upper lip, so that he plays high on the mouthpiece.
Doc Severinsen is a famous Type IV player.
A person is basically born with one embouchure or the other, so a person needs to find out which embouchure type he was born with and go with that.
Any band director who teaches that all players should play with the same embouchure type is just plain ignorant.
Perhaps you could print out the above Web page and give it to him?
You absolutely should NOT "tilt" your head back while playing.
The chin should be *slightly* lowered towards the chest but not touching the chest (3 inches above the chest?), with the head moved *slightly* back in order open the throat better.
Moving the head slightly back while keeping the chin slightly down, which means that you shouldn't "tilt" your head back but rather "slide" your head back *slightly* (an inch?).
ChaseFan