Bach 3 vs Bach 6½AM (small shank)
The Bach 3 has a wider cup diameter, the Bach 6½AM (small shank) has a larger throat opening.
The narrowest point at the bottom of the cup. Affects resistance, volume, and tone color.
Mouthpiece A
Bach 3
• Baritone / Euphonium
Throat diameter5.85 mm / 0.2303 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
vs
Mouthpiece B
Bach 6½AM (small shank)
• Baritone / Euphonium
Throat diameter6.53 mm / 0.2571 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
Throat Diameter
The Bach 6½AM (small shank) has a wider throat (6.53 mm / 0.2571 in vs 5.85 mm / 0.2303 in). 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.