Which has a bigger cup — Bach 18 or Schilke 66?

The Bach 18 has a cup diameter of 32.10 mm / 1.2638 in compared to 31.52 mm / 1.2409 in on the Schilke 66 — a difference of 0.58 mm / 0.0228 in. A wider cup generally produces a fuller, darker tone but requires more air support.

How does cup depth compare between Bach 18 and Schilke 66?

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

Bach 18 vs Schilke 66

Name: Schilke 66
Brand: Schilke

The Bach 18 has a wider cup diameter, the Bach 18 has a larger throat opening.

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

The taper behind the throat leading to the shank. Affects projection and tone character.

Mouthpiece A

Bach 18

• Tuba

Backbore—

Best suited for

📣High-volume projection — open throat for power

Mouthpiece B

Schilke 66

• Tuba

Backbore21/64.3281"

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.