Schilke 13B vs Yamaha TR-14C4
The Yamaha TR-14C4 has a wider cup diameter, the Schilke 13B features a deeper cup.
Cup Diameter
The Yamaha TR-14C4 has a cup diameter of 16.88 mm / 0.6646 in compared to 16.77 mm / 0.6602 in on the Schilke 13B — a difference of 0.11 mm / 0.0043 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Schilke 13B has a deep cup while the Yamaha TR-14C4 has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
Throat diameters are essentially identical at 3.65 mm / 0.1437 in, so resistance feel will be comparable.
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.