I have been playing Carmina Burana for two weeks now (!!) with the Berliner Symphoniker, here in Berlin.
Quite a big piece and fun to play.
I have seen a question regarding the range in the bass trombone part. Some notes are high up there for us, including a long Bb starting piano and lasting for 3 while bars.
The question is : do you take it down an octave ?
The answer is pretty simple. If you are able to nail it, piano, without standing out from the section, yes.
If you’re playing it but crack it most times and have to play really loud, put it down the octave.
That goes for every piece where range interferes with the music.
As I point out in all my range videos:
Good range is being able to play in all registers INSIDE A MUSICAL CONTEXT
If this is not the case, take it down.
Don’t feel ashamed or guilty. This is where you are at the moment.
Accept it, and commit to progress a little more everyday.
You’ll get there !