Bach 5MV vs Bach 6BM
The Bach 5MV has a wider cup diameter, the Bach 5MV has a larger throat opening.
Mouthpiece A
Bach 5MV
• Cornet
Cup diameter16.25 mm / 0.6398 in
Cup depthDeep
Rim width—
Throat diameter3.81 mm / 0.1500 in
Backbore—
Finish—
Material—
Best suited for
High-volume projection — open throat for power
vs
Mouthpiece B
Bach 6BM
• Cornet
Cup diameter16.20 mm / 0.6378 in
Cup depthDeep
Rim width—
Throat diameter3.73 mm / 0.1469 in
Backbore—
Finish—
Material—
Cup Diameter
The Bach 5MV has a cup diameter of 16.25 mm / 0.6398 in compared to 16.20 mm / 0.6378 in on the Bach 6BM — 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
The Bach 5MV has a wider throat (3.81 mm / 0.1500 in vs 3.73 mm / 0.1469 in). A wider throat allows more air through, increasing volume and projection but reducing resistance.
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.