GR Technologies G66FD Radtke vs Schilke 20F
The Schilke 20F has a wider cup diameter, the GR Technologies G66FD Radtke features a deeper cup.
Mouthpiece A
GR Technologies G66FD Radtke
• Flugelhorn
Cup diameter16.76 mm / 0.6598 in
Cup depthDeep
Rim width—
Throat diameter—
Backbore—
Finish—
Material—
vs
Mouthpiece B
Schilke 20F
• Flugelhorn
Cup diameter17.78 mm / 0.7000 in
Cup depthMedium
Rim width—
Throat diameter3.86 mm / 0.1520 in
Backbore24 .1520"
Finish—
Material—
Best suited for
High-volume projection — open throat for power
Cup Diameter
The Schilke 20F has a cup diameter of 17.78 mm / 0.7000 in compared to 16.76 mm / 0.6598 in on the GR Technologies G66FD Radtke — a difference of 1.02 mm / 0.0402 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The GR Technologies G66FD Radtke has a deep cup while the Schilke 20F 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.