GR Technologies 65SZ vs Yamaha TR-14B4
The Yamaha TR-14B4 has a wider cup diameter.
Mouthpiece A
GR Technologies 65SZ
• Trumpet
Cup diameter16.50 mm / 0.6496 in
Cup depthShallow
Rim width—
Throat diameter—
Backbore—
Finish—
Material—
vs
Mouthpiece B
Yamaha TR-14B4
• Trumpet
Cup diameter16.85 mm / 0.6634 in
Cup depthShallow
Rim width—
Throat diameter3.65 mm / 0.1437 in
BackboreSemi-narrow
Finish—
Material—
Cup Diameter
The Yamaha TR-14B4 has a cup diameter of 16.85 mm / 0.6634 in compared to 16.50 mm / 0.6496 in on the GR Technologies 65SZ — a difference of 0.35 mm / 0.0138 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a shallow cup depth, so the sound character from depth alone will be very similar.
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.