Bach 4G vs Bach 4GB
Both mouthpieces share similar core dimensions — the differences are in the details.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bach 4G
• Trombone
Cup diameter26.00 mm / 1.0236 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
vs
Mouthpiece B
Bach 4GB
• Trombone
Cup diameter26.00 mm / 1.0236 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
Cup Diameter
Both mouthpieces have virtually identical cup diameters at 26.00 mm / 1.0236 in.
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.