Bob Reeves DR DINO vs Yamaha AH-38D4
The Bob Reeves DR DINO has a wider cup diameter, the Yamaha AH-38D4 features a deeper cup.
Mouthpiece A
Bob Reeves DR DINO
• Baritone / Euphonium
Cup diameter25.55 mm / 1.0059 in
Cup depthMedium
Rim width—
Throat diameter—
Backbore—
Finish—
Material—
vs
Mouthpiece B
Yamaha AH-38D4
• Baritone / Euphonium
Cup diameter18.90 mm / 0.7441 in
Cup depthDeep
Rim width—
Throat diameter5.25 mm / 0.2067 in
BackboreStandard
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
Cup Diameter
The Bob Reeves DR DINO has a cup diameter of 25.55 mm / 1.0059 in compared to 18.90 mm / 0.7441 in on the Yamaha AH-38D4 — a difference of 6.65 mm / 0.2618 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Yamaha AH-38D4 has a deep cup while the Bob Reeves DR DINO has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
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.