Bach 5GS (large shank) vs Schilke 45B
The Bach 5GS (large shank) has a wider cup diameter, the Bach 5GS (large shank) features a deeper cup, the Bach 5GS (large shank) has a larger throat opening.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bach 5GS (large shank)
• Trombone
Cup diameter25.50 mm / 1.0039 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
vs
Mouthpiece B
Schilke 45B
• Trombone
Cup diameter24.30 mm / 0.9567 in
Best suited for
High-volume projection — open throat for power
Cup Diameter
The Bach 5GS (large shank) has a cup diameter of 25.50 mm / 1.0039 in compared to 24.30 mm / 0.9567 in on the Schilke 45B — a difference of 1.20 mm / 0.0472 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.