Bach 8 vs Yamaha EP-51DL
The Yamaha EP-51DL has a wider cup diameter, the Yamaha EP-51DL features a deeper cup, the Yamaha EP-51DL has a larger throat opening.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bach 8
• Baritone / Euphonium
Cup diameter24.75 mm / 0.9744 in
Best suited for
High-volume projection — open throat for power
vs
Mouthpiece B
Yamaha EP-51DL
• Baritone / Euphonium
Cup diameter25.24 mm / 0.9937 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
Cup Diameter
The Yamaha EP-51DL has a cup diameter of 25.24 mm / 0.9937 in compared to 24.75 mm / 0.9744 in on the Bach 8 — a difference of 0.49 mm / 0.0193 in. A wider cup generally produces a fuller, darker tone but requires more air support.
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.