Kelly 4B-UK vs Kelly 6V
The Kelly 4B-UK has a wider cup diameter, the Kelly 6V 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 4B-UK
• Cornet
OrchestralMaterialLexan polycarbonate
Best suited for
High-volume projection — open throat for power
Professional cornet; British brass band
vs
Mouthpiece B
Kelly 6V
• Cornet
Dark/DeepMaterialLexan polycarbonate
Best suited for
High-volume projection — open throat for power
Deep V-cup to fill out cornet sound
Material
Both mouthpieces share the same listed material (Lexan polycarbonate).
Which is better?
The Kelly 4B-UK is designed for orchestral playing, while the Kelly 6V targets dark/deep use. Your best choice depends on your musical context.