Bach 12E vs Yamaha SL-48L-GP
The Yamaha SL-48L-GP has a wider cup diameter, the Yamaha SL-48L-GP features a deeper cup, the Yamaha SL-48L-GP has a larger throat opening.
The narrowest point at the bottom of the cup. Affects resistance, volume, and tone color.
Mouthpiece A
Bach 12E
• Trombone
Throat diameter5.85 mm / 0.2303 in
Best suited for
High-volume projection — open throat for power
vs
Mouthpiece B
Yamaha SL-48L-GP
• Trombone
Throat diameter6.62 mm / 0.2606 in
Best suited for
High-volume projection — open throat for power
Throat Diameter
The Yamaha SL-48L-GP has a wider throat (6.62 mm / 0.2606 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.