Bach 1½C vs Conn Connstellation 7CN
The Bach 1½C has a wider cup diameter, the Conn Connstellation 7CN features a deeper cup.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bach 1½C
• Cornet
Cup diameter17.00 mm / 0.6693 in
vs
Mouthpiece B
Conn Connstellation 7CN
• Cornet
GeneralCup diameter16.42 mm / 0.6465 in
Best suited for
Trumpet players seeking precise matched dimensions
Size 7 (16.42mm); larger cup; fuller lower register; Narrow rim; smaller inner radius; sharper bite.
Cup Diameter
The Bach 1½C has a cup diameter of 17.00 mm / 0.6693 in compared to 16.42 mm / 0.6465 in on the Conn Connstellation 7CN — a difference of 0.58 mm / 0.0228 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.