Bach 3 vs Yamaha EP-51DL
The Bach 3 has a wider cup diameter, the Yamaha EP-51DL has a larger throat opening.
Mouthpiece A
Bach 3
• Baritone / Euphonium
Cup diameter26.26 mm
Cup depthDeep
Rim width—
Throat diameter5.85 mm
Backbore—
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
vs
Mouthpiece B
Yamaha EP-51DL
• Baritone / Euphonium
Cup diameter25.24 mm
Cup depthDeep
Rim width—
Throat diameter7.11 mm
BackboreStandard
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
Cup Diameter
The Bach 3 has a cup diameter of 26.26 mm compared to 25.24 mm on the Yamaha EP-51DL — a difference of +1.02 mm. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a deep cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
The Yamaha EP-51DL has a wider throat (7.11 mm vs 5.85 mm). A wider throat allows more air through, increasing volume and projection but reducing resistance.
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.