Giardinelli 18 vs Schilke GEIB
The Schilke GEIB has a wider cup diameter, the Giardinelli 18 features a deeper cup.
Cup Diameter
The Schilke GEIB has a cup diameter of 32.76 mm / 1.2898 in compared to 31.00 mm / 1.2205 in on the Giardinelli 18 — a difference of 1.76 mm / 0.0693 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Giardinelli 18 has a deep cup while the Schilke GEIB has a shallow 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 7.95 mm / 0.3130 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.