Good mouthpiece?

[Trombone82]

I have an old 12c that I can go past high Bb on and a new bach 6.5 AL that I can't consistently get to high A on. I love the richness of the 6.5 AL but I was wondering if there's a mouthpiece where I can get the best of both worlds. I've been practicing mostly on the 6.5 AL for the last few months but still can't get my range up as much as I want.

[BGuttman]

This is a common complaint. Small mouthpieces tend to help high range at the expense of lower range. Larger mouthpieces tend to be more sonorous at the expense of high range.

The solution is to do rangebuilding exercises on the larger mouthpieces. As your embouchure becomes stronger the high notes will be easier. This is what we ALL did. It's not just you.

[WGWTR180]

Sounds like you need to spend a LOT of time practicing on whichever mouthpiece you pick and stick with it for months. Bruce's idea of range building exercises is spot on. Done properly your range will increase. If you find yourself having zero success find a teacher to make sure you're doing everything properly.

[JTeagarden]

Since we know nothing about the OP, all bets are off as regards what advice actually makes sense: How long have they been playing, what horn do they play, on and on.

He or she might as well be asking what shoes will fit best.

[ssking2b]

Bach 6 3/4 C, or Bach 7C, or Bach 11C
It's also about getting the right sound for the horn you are playing. Smaller pieces aren't necessarily the whole issue. You can get a wider rim with a shallower cup from Doug Elliot.