Bach 19 vs Yamaha SL-48DL
The Yamaha SL-48DL has a wider cup diameter, the Yamaha SL-48DL has a larger throat opening.
The narrowest point at the bottom of the cup. Affects resistance, volume, and tone color.
Mouthpiece A
Bach 19
• Trombone
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
Yamaha SL-48DL
• Trombone
Throat diameter6.62 mm / 0.2606 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
Throat Diameter
The Yamaha SL-48DL 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.