Which has a bigger cup — Bach 14D or Bach 15C?

The Bach 14D has a cup diameter of 24.50 mm / 0.9646 in compared to 24.40 mm / 0.9606 in on the Bach 15C — 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 14D and Bach 15C?

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

Bach 14D vs Bach 15C

Name: Bach 15C
Brand: Bach

The Bach 14D has a wider cup diameter.

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

The narrowest point at the bottom of the cup. Affects resistance, volume, and tone color.

Mouthpiece A

Bach 14D

• Trombone

Throat diameter5.85 mm / 0.2303 in

Best suited for

📣High-volume projection — open throat for power

Mouthpiece B

Bach 15C

• Trombone

Throat diameter5.85 mm / 0.2303 in

Best suited for

📣High-volume projection — open throat for power

Throat Diameter

Throat diameters are essentially identical at 5.85 mm / 0.2303 in, so resistance feel will be comparable.

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 14D details Bach 15C details Bach 14D equivalents Bach 15C equivalents

Bach 14D vs Bach 15C

Throat Diameter

Playing Characteristics

What Do These Model Names Mean?

What Changes If You Switch?

Which is better?

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Compare Bach 15C with others

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