Kelly 24AW vs Schilke S-H
The Schilke S-H has a wider cup diameter, the Kelly 24AW features a deeper cup.
Cup Diameter
The Schilke S-H has a cup diameter of 31.84 mm / 1.2535 in compared to 31.24 mm / 1.2299 in on the Kelly 24AW — a difference of 0.60 mm / 0.0236 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Kelly 24AW has a very deep cup while the Schilke S-H has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Material
The Kelly 24AW is described as Lexan polycarbonate, and the Schilke S-H as unspecified. Material affects mass, warmth, and how quickly the piece responds.
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.