Marcinkiewicz 304 vs Marcinkiewicz 306
Both mouthpieces share similar core dimensions — the differences are in the details.
Mouthpiece A
Marcinkiewicz 304
• Cornet
Cup diameter17.20 mm / 0.6772 in
Cup depthShallow
Rim width—
Throat diameter3.73 mm / 0.1469 in
Backbore—
Finish—
Material—
vs
Mouthpiece B
Marcinkiewicz 306
• Cornet
Cup diameter17.20 mm / 0.6772 in
Cup depthShallow
Rim width—
Throat diameter3.73 mm / 0.1469 in
Backbore—
Finish—
Material—
Cup Diameter
Both mouthpieces have virtually identical cup diameters at 17.20 mm / 0.6772 in.
Cup Depth
Both mouthpieces share a shallow cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
Throat diameters are essentially identical at 3.73 mm / 0.1469 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.