Bach 6½AL (large shank) vs Bob Reeves 5G/JF
The Bob Reeves 5G/JF has a wider cup diameter.
Mouthpiece A
Bach 6½AL (large shank)
• Trombone
Cup diameter25.40 mm / 1.0000 in
Cup depthDeep
Rim width—
Throat diameter6.63 mm / 0.2610 in
Backbore—
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
vs
Mouthpiece B
Bob Reeves 5G/JF
• Trombone
Cup diameter25.55 mm / 1.0059 in
Cup depthDeep
Rim width—
Throat diameter—
Backbore—
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
Cup Diameter
The Bob Reeves 5G/JF has a cup diameter of 25.55 mm / 1.0059 in compared to 25.40 mm / 1.0000 in on the Bach 6½AL (large shank) — a difference of 0.15 mm / 0.0059 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.