Yamaha CR-11B4L vs Yamaha CR-11E4S
The Yamaha CR-11B4L has a wider cup diameter, the Yamaha CR-11E4S features a deeper cup, the Yamaha CR-11E4S has a larger throat opening.
Cup Diameter
The Yamaha CR-11B4L has a cup diameter of 16.64 mm / 0.6551 in compared to 16.46 mm / 0.6480 in on the Yamaha CR-11E4S — a difference of 0.18 mm / 0.0071 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Yamaha CR-11E4S has a very deep cup while the Yamaha CR-11B4L has a shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Yamaha CR-11E4S has a wider throat (4.20 mm / 0.1654 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.