Which has a bigger cup — Bach 8½A or Yamaha CR-9ES?

The Yamaha CR-9ES has a cup diameter of 16.44 mm / 0.6472 in compared to 16.10 mm / 0.6339 in on the Bach 8½A — a difference of 0.34 mm / 0.0134 in. A wider cup generally produces a fuller, darker tone but requires more air support.

How does cup depth compare between Bach 8½A and Yamaha CR-9ES?

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

Bach 8½A vs Yamaha CR-9ES

Name: Yamaha CR-9ES
Brand: Yamaha

The Yamaha CR-9ES has a wider cup diameter, the Yamaha CR-9ES has a larger throat opening.

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 8½A

• Cornet

Rim width—

Mouthpiece B

Yamaha CR-9ES

• Cornet

Rim width—

Best suited for

📣High-volume projection — open throat for power

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.