For posture: stand tall and bring the horn to you.
For most people, this will result in the horn angling down a bit.
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Ahhh, marching band season when so many are told to angle 10 degrees above horizontal (or something like that).
How to resolve this problem?
No perfect solution but I guess bending at the waist is the least bad.
This raises a question that seemed dumb at first but......
Why is the bell angled the way it is? What if the bell angled up a bit.
I'm not talking a "Dizzy Gillespie" angle..
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But still, what if the bell angled up a bit? How dumb is this idea?
For that matter, what if the slide angled slightly to the right? Wouldn't that make the longer positions easier to reach?
Worth considering, I think.