Which has a bigger cup — Bach 11½A or Bach 12?

The Bach 11½A has a cup diameter of 15.65 mm / 0.6161 in compared to 15.20 mm / 0.5984 in on the Bach 12 — a difference of 0.45 mm / 0.0177 in. A wider cup generally produces a fuller, darker tone but requires more air support.

Bach 11½A vs Bach 12

Name: Bach 12
Brand: Bach

The Bach 11½A 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 11½A

• Cornet

Cup depthVery deep

Mouthpiece B

Bach 12

• Cornet

Cup depthVery deep

Cup Depth

Both mouthpieces share a very 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.