Conn Precision 3 vs Kelly 3C
The Kelly 3C has a wider cup diameter, the Kelly 3C features a deeper cup.
How deep the cup is, from shallow (brighter, easier high register) to deep (darker, fuller sound).
Mouthpiece A
Conn Precision 3
• Cornet
GeneralCup depthMedium
Best suited for
All-round versatile — balanced cup for general playing
All-around use; most popular model
Bright quality of tone in all registers; good all-around
vs
Mouthpiece B
Kelly 3C
• Cornet
GeneralCup depthVery deep
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
All-purpose mid-range
Cup Depth
The Kelly 3C has a very deep cup while the Conn Precision 3 has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Which is better?
Both mouthpieces are categorized as "General" — the physical dimensions above will determine which suits your embouchure and playing style better.