Bach 1B vs Bach 9D
The Bach 1B has a wider cup diameter, the Bach 1B features a deeper cup.
The width of the rim surface that contacts the lips. Wider rims improve endurance; narrower rims improve flexibility.
Mouthpiece A
Bach 1B
• Cornet
Rim width—
Best suited for
Orchestral playing — large cup for full, dark tone
vs
Mouthpiece B
Bach 9D
• Cornet
Rim width—
Best suited for
Lead / commercial — shallow cup for brightness and range
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.