Marcinkiewicz 1 / 5B vs Marcinkiewicz 3 / 5C
The Marcinkiewicz 1 / 5B has a wider cup diameter.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Marcinkiewicz 1 / 5B
• Cornet
Cup diameter17.35 mm / 0.6831 in
vs
Mouthpiece B
Marcinkiewicz 3 / 5C
• Cornet
Cup diameter17.20 mm / 0.6772 in
Cup Diameter
The Marcinkiewicz 1 / 5B has a cup diameter of 17.35 mm / 0.6831 in compared to 17.20 mm / 0.6772 in on the Marcinkiewicz 3 / 5C — a difference of 0.15 mm / 0.0059 in. A wider cup generally produces a fuller, darker tone but requires more air support.
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.