Bob Reeves 40/SV/X vs Schilke 13A4a
The Schilke 13A4a has a wider cup diameter.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bob Reeves 40/SV/X
• Trumpet
Cup diameter15.88 mm / 0.6252 in
Best suited for
Lead / commercial — shallow cup for brightness and range
vs
Mouthpiece B
Schilke 13A4a
• Trumpet
Cup diameter16.76 mm / 0.6598 in
Cup Diameter
The Schilke 13A4a has a cup diameter of 16.76 mm / 0.6598 in compared to 15.88 mm / 0.6252 in on the Bob Reeves 40/SV/X — a difference of 0.88 mm / 0.0346 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.