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.

How does cup depth compare between Bach 8½B and Bach 9B?

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

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

The width of the rim surface that contacts the lips. Wider rims improve endurance; narrower rims improve flexibility.

Mouthpiece A

Bach 8½B

• Cornet

Rim width—

Mouthpiece B

Bach 9B

• Cornet

Rim width—

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.