Schilke 51D vs Yamaha EP-51DS
The Schilke 51D has a wider cup diameter, the Yamaha EP-51DS features a deeper cup, the Yamaha EP-51DS has a larger throat opening.
Cup Diameter
The Schilke 51D has a cup diameter of 25.55 mm / 1.0059 in compared to 25.24 mm / 0.9937 in on the Yamaha EP-51DS — a difference of 0.31 mm / 0.0122 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Yamaha EP-51DS has a deep cup while the Schilke 51D has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Yamaha EP-51DS has a wider throat (7.11 mm / 0.2799 in vs 7.04 mm / 0.2772 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.