Yamaha TR-11B4-GP vs Yamaha TR-13B4
The Yamaha TR-13B4 has a wider cup diameter.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Yamaha TR-11B4-GP
• Trumpet
Cup diameter16.46 mm / 0.6480 in
vs
Mouthpiece B
Yamaha TR-13B4
• Trumpet
Cup diameter16.63 mm / 0.6547 in
Cup Diameter
The Yamaha TR-13B4 has a cup diameter of 16.63 mm / 0.6547 in compared to 16.46 mm / 0.6480 in on the Yamaha TR-11B4-GP — a difference of 0.17 mm / 0.0067 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.