Kelly SCREAMER vs Marcinkiewicz 5*W (Endorsee)
The Marcinkiewicz 5*W (Endorsee) has a wider cup diameter, the Kelly SCREAMER features a deeper cup, the Marcinkiewicz 5*W (Endorsee) has a larger throat opening.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Kelly SCREAMER
• Cornet
LeadCup diameter16.00 mm / 0.6299 in
Best suited for
Lead / commercial — shallow cup for brightness and range
Screamer / high notes — tight throat with shallow cup
Lead / soprano cornet
vs
Mouthpiece B
Marcinkiewicz 5*W (Endorsee)
• Cornet
Cup diameter16.76 mm / 0.6598 in
Best suited for
High-volume projection — open throat for power
Cup Diameter
The Marcinkiewicz 5*W (Endorsee) has a cup diameter of 16.76 mm / 0.6598 in compared to 16.00 mm / 0.6299 in on the Kelly SCREAMER — a difference of 0.76 mm / 0.0299 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.