Yamaha SL-51C4S vs Yamaha SL-51L
Both mouthpieces share similar core dimensions — the differences are in the details.
Mouthpiece A
Yamaha SL-51C4S
• Trombone
Cup diameter25.23 mm / 0.9933 in
Cup depthMedium
Rim width—
Throat diameter6.92 mm / 0.2724 in
BackboreSemi-wide
Finish—
Material—
Best suited for
High-volume projection — open throat for power
vs
Mouthpiece B
Yamaha SL-51L
• Trombone
Cup diameter25.23 mm / 0.9933 in
Cup depthMedium
Rim width—
Throat diameter6.92 mm / 0.2724 in
BackboreSemi-wide
Finish—
Material—
Best suited for
High-volume projection — open throat for power
Cup Diameter
Both mouthpieces have virtually identical cup diameters at 25.23 mm / 0.9933 in.
Cup Depth
Both mouthpieces share a medium cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
Throat diameters are essentially identical at 6.92 mm / 0.2724 in, so resistance feel will be comparable.
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.