Which has a bigger cup — Giardinelli Sym. T or Kelly 12C?

The Giardinelli Sym. T has a cup diameter of 25.80 mm / 1.0157 in compared to 24.13 mm / 0.9500 in on the Kelly 12C — a difference of 1.67 mm / 0.0657 in. A wider cup generally produces a fuller, darker tone but requires more air support.

How does cup depth compare between Giardinelli Sym. T and Kelly 12C?

The Giardinelli Sym. T has a deep cup while the Kelly 12C has a shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.

Giardinelli Sym. T vs Kelly 12C

Name: Kelly 12C
Brand: Kelly

The Giardinelli Sym. T has a wider cup diameter, the Giardinelli Sym. T features a deeper cup.

Overall Comparison Cup Diameter Cup Depth Rim Width Throat Diameter Backbore Finish Material

The narrowest point at the bottom of the cup. Affects resistance, volume, and tone color.

Mouthpiece A

Giardinelli Sym. T

• Trombone

Throat diameter6.40 mm / 0.2520 in

Best suited for

🎻Orchestral playing — large cup for full, dark tone

📣High-volume projection — open throat for power

Mouthpiece B

Kelly 12C

• Trombone

Lead

Throat diameter—

Best suited for

📋Lead trombone; smallest cup

Which is better?

Neither mouthpiece clearly dominates the other — the right choice depends on your embouchure, playing style, and the sound you're after. Try both if possible.

Open in interactive tool + Add third mouthpiece Giardinelli Sym. T details Kelly 12C details Giardinelli Sym. T equivalents Kelly 12C equivalents

Giardinelli Sym. T vs Kelly 12C

Playing Characteristics

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