Which has a bigger cup — Bach 12E or Bach 15CW?

The Bach 12E has a cup diameter of 24.50 mm / 0.9646 in compared to 24.40 mm / 0.9606 in on the Bach 15CW — a difference of 0.10 mm / 0.0039 in. A wider cup generally produces a fuller, darker tone but requires more air support.

Bach 12E vs Bach 15CW

Name: Bach 15CW
Brand: Bach

The Bach 12E has a wider cup diameter.

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

How deep the cup is, from shallow (brighter, easier high register) to deep (darker, fuller sound).

Mouthpiece A

Bach 12E

• Trombone

Cup depthShallow

Best suited for

📣High-volume projection — open throat for power

Mouthpiece B

Bach 15CW

• Trombone

Cup depthShallow

Best suited for

📣High-volume projection — open throat for power

Cup Depth

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

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.

Open in interactive tool + Add third mouthpiece Bach 12E details Bach 15CW details Bach 12E equivalents Bach 15CW equivalents

Bach 12E vs Bach 15CW

Cup Depth

Playing Characteristics

What Do These Model Names Mean?

What Changes If You Switch?

Which is better?

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Compare Bach 15CW with others

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