Which has a bigger cup — Bach 3D or Bach 7D?

The Bach 3D has a cup diameter of 16.30 mm / 0.6417 in compared to 16.20 mm / 0.6378 in on the Bach 7D — a difference of 0.10 mm / 0.0039 in. A wider cup generally produces a fuller, darker tone but requires more air support.

How does cup depth compare between Bach 3D and Bach 7D?

Both mouthpieces share a shallow cup depth, so the sound character from depth alone will be very similar.

Bach 3D vs Bach 7D

Name: Bach 7D
Brand: Bach

The Bach 3D has a wider cup diameter.

Overall Comparison Cup Diameter Cup Depth Rim Width Throat Diameter Backbore Finish Material

The width of the rim surface that contacts the lips. Wider rims improve endurance; narrower rims improve flexibility.

Mouthpiece A

Bach 3D

• Cornet

Rim width—

Mouthpiece B

Bach 7D

• 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.