Conn Precision 4 vs Yamaha SL-48L
the Conn Precision 4 features a deeper cup.
Mouthpiece A
Conn Precision 4
• Trombone
OrchestralCup diameter—
Cup depth
Rim width—
Throat diameter—
Backbore—
Finish—
MaterialSilver-plated brass
Best suited for
Bass trombone
Full rich deep tone quality
vs
Mouthpiece B
Yamaha SL-48L
• Trombone
Cup diameter25.25 mm / 0.9941 in
Cup depthMedium
Rim width—
Throat diameter6.62 mm / 0.2606 in
BackboreSemi-narrow
Finish—
Material—
Best suited for
High-volume projection — open throat for power
Cup Depth
The Conn Precision 4 has a — cup while the Yamaha SL-48L has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Material
The Conn Precision 4 is described as Silver-plated brass, and the Yamaha SL-48L as unspecified. Material affects mass, warmth, and how quickly the piece responds.
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.