Bach 11½A vs Monette Cornet B2 FL
The Monette Cornet B2 FL has a wider cup diameter, the Bach 11½A features a deeper cup.
Cup Diameter
The Monette Cornet B2 FL has a cup diameter of 17.00 mm / 0.6693 in compared to 15.65 mm / 0.6161 in on the Bach 11½A — a difference of 1.35 mm / 0.0531 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Bach 11½A has a very deep cup while the Monette Cornet B2 FL has a deep 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 3.66 mm / 0.1441 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.