Bach 3C vs Yamaha TR-11A4
The Yamaha TR-11A4 has a wider cup diameter, the Bach 3C features a deeper cup, the Bach 3C has a larger throat opening.
Cup Diameter
The Yamaha TR-11A4 has a cup diameter of 16.46 mm / 0.6480 in compared to 16.30 mm / 0.6417 in on the Bach 3C — a difference of 0.16 mm / 0.0063 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Bach 3C has a medium cup while the Yamaha TR-11A4 has a very shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Bach 3C has a wider throat (3.66 mm / 0.1441 in vs 3.65 mm / 0.1437 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.