Bach 9 vs Giardinelli 5M
The Giardinelli 5M has a wider cup diameter, the Bach 9 features a deeper cup, the Giardinelli 5M has a larger throat opening.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bach 9
• Baritone / Euphonium
Cup diameter24.72 mm / 0.9732 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
vs
Mouthpiece B
Giardinelli 5M
• Baritone / Euphonium
Cup diameter25.00 mm / 0.9843 in
Best suited for
High-volume projection — open throat for power
Cup Diameter
The Giardinelli 5M has a cup diameter of 25.00 mm / 0.9843 in compared to 24.72 mm / 0.9732 in on the Bach 9 — a difference of 0.28 mm / 0.0110 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.