Which has a bigger cup — Bach 8½B or Bach 9B?

The Bach 8½B has a cup diameter of 16.10 mm / 0.6339 in compared to 16.05 mm / 0.6319 in on the Bach 9B — a difference of 0.05 mm / 0.0020 in. A wider cup generally produces a fuller, darker tone but requires more air support.

Bach 8½B vs Bach 9B

Name: Bach 9B
Brand: Bach

The Bach 8½B has a wider cup diameter.

Overall Comparison Cup Diameter Cup Depth Rim Width Throat Diameter Backbore Finish Material

How deep the cup is, from shallow (brighter, easier high register) to deep (darker, fuller sound).

Mouthpiece A

Bach 8½B

• Cornet

Cup depthDeep

Mouthpiece B

Bach 9B

• Cornet

Cup depthDeep

Cup Depth

Both mouthpieces share a deep cup depth, so the sound character from depth alone will be very similar.

Which is better?

Neither mouthpiece clearly dominates the other — the right choice depends on your embouchure, playing style, and the sound you're after. Try both if possible.