Conn Imp. Precision 1 vs Conn Imp. Precision 4
the Conn Imp. Precision 4 features a deeper cup.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Conn Imp. Precision 1
• Trombone
OrchestralCup diameter—
Best suited for
Large bore trombones; symphony
Good clear tone; large bore symphonic
vs
Mouthpiece B
Conn Imp. Precision 4
• Trombone
OrchestralCup diameter—
Best suited for
Bass trombone / large bore tenor
Full rich deep tone
Which is better?
Both mouthpieces are categorized as "Orchestral" — the physical dimensions above will determine which suits your embouchure and playing style better.