Bach 11¾C vs Bach 11B
The Bach 11B has a wider cup diameter, the Bach 11B features a deeper cup.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bach 11¾C
• Cornet
Cup diameter15.60 mm / 0.6142 in
vs
Mouthpiece B
Bach 11B
• Cornet
Cup diameter15.70 mm / 0.6181 in
Cup Diameter
The Bach 11B has a cup diameter of 15.70 mm / 0.6181 in compared to 15.60 mm / 0.6142 in on the Bach 11¾C — a difference of 0.10 mm / 0.0039 in. A wider cup generally produces a fuller, darker tone but requires more air support.
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.