Bach 10½D vs Bach 11EW
The Bach 10½D has a wider cup diameter.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bach 10½D
• Cornet
Cup diameter15.90 mm / 0.6260 in
Best suited for
Lead / commercial — shallow cup for brightness and range
vs
Mouthpiece B
Bach 11EW
• Cornet
Cup diameter15.70 mm / 0.6181 in
Best suited for
Lead / commercial — shallow cup for brightness and range
Cup Diameter
The Bach 10½D has a cup diameter of 15.90 mm / 0.6260 in compared to 15.70 mm / 0.6181 in on the Bach 11EW — a difference of 0.20 mm / 0.0079 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.