Bach 3C vs Schilke D2
The Schilke D2 has a wider cup diameter, the Schilke D2 features a deeper cup, the Schilke D2 has a larger throat opening.
Cup Diameter
The Schilke D2 has a cup diameter of 17.27 mm / 0.6799 in compared to 16.30 mm / 0.6417 in on the Bach 3C — a difference of 0.97 mm / 0.0382 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Schilke D2 has a deep cup while the Bach 3C has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Schilke D2 has a wider throat (3.84 mm / 0.1512 in vs 3.66 mm / 0.1441 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.