Conn Imp. Precision 3 vs Kelly 18
the Conn Imp. Precision 3 features a deeper cup.
Mouthpiece A
Conn Imp. Precision 3
• Tuba
GeneralCup diameter—
Cup depth
Rim width—
Throat diameter—
Backbore—
Finish—
MaterialSilver-plated brass
Best suited for
Large Eb bass
Full round tone
vs
Mouthpiece B
Kelly 18
• Tuba
GeneralCup diameter32.77 mm / 1.2902 in
Cup depth
Rim width—
Throat diameter—
BackboreM
Finish—
MaterialLexan polycarbonate
Best suited for
Orchestral playing — large cup for full, dark tone
Industry-standard tuba
Cup Depth
The Conn Imp. Precision 3 has a — cup while the Kelly 18 has a — cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Material
The Conn Imp. Precision 3 is described as Silver-plated brass, and the Kelly 18 as Lexan polycarbonate. Material affects mass, warmth, and how quickly the piece responds.
Which is better?
Both mouthpieces are categorized as "General" — the physical dimensions above will determine which suits your embouchure and playing style better.