GR Technologies G66FD Radtke vs GR Technologies 67FD
The GR Technologies 67FD has a wider cup diameter.
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
GR Technologies 67FD
• Flugelhorn
Cup diameter17.00 mm / 0.6693 in
Cup depthDeep
Rim width—
Throat diameter—
Backbore—
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
Cup Diameter
The GR Technologies 67FD has a cup diameter of 17.00 mm / 0.6693 in compared to 16.76 mm / 0.6598 in on the GR Technologies G66FD Radtke — a difference of 0.24 mm / 0.0094 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a deep 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.