Bach 18C vs Denis Wick SM4M
The Denis Wick SM4M has a wider cup diameter, the Denis Wick SM4M features a deeper cup, the Denis Wick SM4M has a larger throat opening.
Cup Diameter
The Denis Wick SM4M has a cup diameter of 26.00 mm / 1.0236 in compared to 24.20 mm / 0.9528 in on the Bach 18C — a difference of 1.80 mm / 0.0709 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Denis Wick SM4M has a very deep cup while the Bach 18C has a shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Denis Wick SM4M has a wider throat (7.38 mm / 0.2906 in vs 5.85 mm / 0.2303 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.