Bach 10 vs Marcinkiewicz CH R 9S
The Marcinkiewicz CH R 9S has a wider cup diameter, the Bach 10 features a deeper cup, the Marcinkiewicz CH R 9S has a larger throat opening.
Cup Diameter
The Marcinkiewicz CH R 9S has a cup diameter of 17.58 mm / 0.6921 in compared to 16.80 mm / 0.6614 in on the Bach 10 — a difference of 0.78 mm / 0.0307 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Bach 10 has a very deep cup while the Marcinkiewicz CH R 9S has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Marcinkiewicz CH R 9S has a wider throat (4.98 mm / 0.1961 in vs 4.50 mm / 0.1772 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.