Bach 8½A vs Bob Reeves 40/B/69
The Bach 8½A has a wider cup diameter.
Mouthpiece A
Bach 8½A
• Cornet
Cup diameter16.10 mm / 0.6339 in
Cup depthVery deep
Rim width—
Throat diameter3.66 mm / 0.1441 in
Backbore—
Finish—
Material—
vs
Mouthpiece B
Bob Reeves 40/B/69
• Cornet
Cup diameter15.88 mm / 0.6252 in
Cup depthVery deep
Rim width—
Throat diameter—
Backbore69
Finish—
Material—
Cup Diameter
The Bach 8½A has a cup diameter of 16.10 mm / 0.6339 in compared to 15.88 mm / 0.6252 in on the Bob Reeves 40/B/69 — a difference of 0.22 mm / 0.0087 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a very 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.