Bach 5B vs Monette Cornet BP4LD FL
The Bach 5B has a wider cup diameter.
Mouthpiece A
Bach 5B
• Cornet
Cup diameter16.25 mm / 0.6398 in
Cup depthDeep
Rim width—
Throat diameter3.66 mm / 0.1441 in
Backbore—
Finish—
Material—
vs
Mouthpiece B
Monette Cornet BP4LD FL
• Cornet
Cup diameter16.20 mm / 0.6378 in
Cup depthDeep
Rim width—
Throat diameter3.66 mm / 0.1441 in
Backbore—
Finish—
Material—
Cup Diameter
The Bach 5B has a cup diameter of 16.25 mm / 0.6398 in compared to 16.20 mm / 0.6378 in on the Monette Cornet BP4LD FL — a difference of 0.05 mm / 0.0020 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.
Throat Diameter
Throat diameters are essentially identical at 3.66 mm / 0.1441 in, so resistance feel will be comparable.
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.