Denis Wick 4B vs Kelly 6V-UK
The Denis Wick 4B has a wider cup diameter, the Kelly 6V-UK features a deeper cup, the Denis Wick 4B has a larger throat opening.
Cup Diameter
The Denis Wick 4B has a cup diameter of 16.50 mm / 0.6496 in compared to 16.00 mm / 0.6299 in on the Kelly 6V-UK — a difference of 0.50 mm / 0.0197 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Kelly 6V-UK has a — cup while the Denis Wick 4B has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Denis Wick 4B has a wider throat (4.27 mm / 0.1681 in vs 4.06 mm / 0.1598 in). A wider throat allows more air through, increasing volume and projection but reducing resistance.
Material
The Denis Wick 4B is described as unspecified, and the Kelly 6V-UK as Lexan polycarbonate. 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.