Marcinkiewicz 15 vs Yamaha HR-29B
The Marcinkiewicz 15 has a wider cup diameter, the Marcinkiewicz 15 features a deeper cup, the Marcinkiewicz 15 has a larger throat opening.
Cup Diameter
The Marcinkiewicz 15 has a cup diameter of 17.42 mm / 0.6858 in compared to 17.07 mm / 0.6720 in on the Yamaha HR-29B — a difference of 0.35 mm / 0.0138 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Marcinkiewicz 15 has a very deep cup while the Yamaha HR-29B has a shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Marcinkiewicz 15 has a wider throat (4.57 mm / 0.1799 in vs 3.90 mm / 0.1535 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.