Denis Wick 9BS vs Yamaha SL-53L
The Yamaha SL-53L has a wider cup diameter, the Yamaha SL-53L has a larger throat opening.
Cup Diameter
The Yamaha SL-53L has a cup diameter of 25.91 mm / 1.0201 in compared to 25.00 mm / 0.9843 in on the Denis Wick 9BS — a difference of 0.91 mm / 0.0358 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a medium cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
The Yamaha SL-53L has a wider throat (7.11 mm / 0.2799 in vs 6.66 mm / 0.2622 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.