TromboneChat

Like saying the letter M
I feel like I'm pinching the tone and there's no room for flexibility when I do that.

As I recall you are upstream, or at least it seems like you are. So some of the things that normally apply to other embouchure types may not apply to you quite the same way.

Don't ever feel like you're pinching... it gives you a pinched sound. And that applies to anybody.

This was a question I was going to ask you during our lesson but never got around to it.
But the upper lip should be firm?

I don't know if there's a good answer to that question.
Not necessarily firm, but definitely not pinched.
Try feeling like you're opening or "unpinching"
Not actually open, but heading in that direction.

I'm an upstream player too, cb56.

Just a guess, but are you pulling your corners back as you ascend? If so, that could be what you're experiencing.

Did Doug teach you how to free buzz in your lesson? If so, that's a great way to practice keeping your mouth corners in place.

Dave

Dave, no I don't pull the corners back.
Put your lips like you're making an M then tighten everything up. That's the feeling I get when I try to play above F 3 spaces above staff.

When I was young (playing an olds super with 12c) I used to have a smile embouchure and I could play high and had super flexibility but my tone was bad and I cracked a lot of notes. Was told to correct that in college , I finally did. Tone improved but range went away.
Many decades of on and off playing ( mostly off) it remains the same.

Doug and I Did do some free buzzing.
He also sent me a mouthpiece set.up to try with 2 different rims. When I found out I needed to get teeth pulled I got discouraged and sent them back.
Also thought about selling my horn.

I bought my 78h from Doug Bert (brass exchange) I went to his shop about a month ago and he encouraged me not to give up. I bought a used 6 1/2 al from him that he suggested for that horn. I played on it for 2 weeks before I got my 2 teeth pulled. I really liked the 6 1/2al even though it's smaller than what DE was having me try. Not sure what Bach the DE mouthpiece would compare to.

A more tight embouchure but not super stiff and fast airflow is what I was told when playing high.