Bruno Tilz 306-9 1/2 GS vs Yamaha SL-YEO-S
The Bruno Tilz 306-9 1/2 GS has a wider cup diameter, the Yamaha SL-YEO-S features a deeper cup, the Yamaha SL-YEO-S has a larger throat opening.
Cup Diameter
The Bruno Tilz 306-9 1/2 GS has a cup diameter of 29.50 mm / 1.1614 in compared to 28.72 mm / 1.1307 in on the Yamaha SL-YEO-S — a difference of 0.78 mm / 0.0307 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Yamaha SL-YEO-S has a deep cup while the Bruno Tilz 306-9 1/2 GS has a shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Yamaha SL-YEO-S has a wider throat (8.00 mm / 0.3150 in vs 7.00 mm / 0.2756 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.