Bob Reeves Piccolo 41/SV/692s vs GR Technologies 64Z**
Both mouthpieces share similar core dimensions — the differences are in the details.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bob Reeves Piccolo 41/SV/692s
• Trumpet
Cup diameter16.27 mm / 0.6406 in
vs
Mouthpiece B
GR Technologies 64Z**
• Trumpet
Cup diameter16.26 mm / 0.6402 in
Cup Diameter
Both mouthpieces have virtually identical cup diameters at 16.27 mm / 0.6406 in.
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.