Bruno Tilz 231-C 4 vs Marcinkiewicz ETU1J. Self
The Marcinkiewicz ETU1J. Self has a wider cup diameter, the Bruno Tilz 231-C 4 features a deeper cup, the Bruno Tilz 231-C 4 has a larger throat opening.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bruno Tilz 231-C 4
• Tuba
CatalogCup diameter33.00 mm / 1.2992 in
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
vs
Mouthpiece B
Marcinkiewicz ETU1J. Self
• Tuba
Cup diameter33.15 mm / 1.3051 in
Best suited for
High-volume projection — open throat for power
Cup Diameter
The Marcinkiewicz ETU1J. Self has a cup diameter of 33.15 mm / 1.3051 in compared to 33.00 mm / 1.2992 in on the Bruno Tilz 231-C 4 — 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.