Kelly 3C vs Kelly 4B-UK
The Kelly 3C has a wider cup diameter, the Kelly 4B-UK features a deeper cup, the Kelly 4B-UK has a larger throat opening.
Base metal or construction (e.g. brass, stainless steel, plastic). Influences weight, response, and tone color.
Mouthpiece A
Kelly 3C
• Cornet
GeneralMaterialLexan polycarbonate
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
All-purpose mid-range
vs
Mouthpiece B
Kelly 4B-UK
• Cornet
OrchestralMaterialLexan polycarbonate
Best suited for
High-volume projection — open throat for power
Professional cornet; British brass band
Material
Both mouthpieces share the same listed material (Lexan polycarbonate).
Which is better?
The Kelly 3C is designed for general playing, while the Kelly 4B-UK targets orchestral use. Your best choice depends on your musical context.