Which has a bigger cup — Bach 6 or Kelly 5G-EU-SS?

The Bach 6 has a cup diameter of 25.50 mm / 1.0039 in compared to 25.40 mm / 1.0000 in on the Kelly 5G-EU-SS — a difference of 0.10 mm / 0.0039 in. A wider cup generally produces a fuller, darker tone but requires more air support.

How does cup depth compare between Bach 6 and Kelly 5G-EU-SS?

The Kelly 5G-EU-SS has a — cup while the Bach 6 has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.

Bach 6 vs Kelly 5G-EU-SS

Name: Kelly 5G-EU-SS
Brand: Kelly

The Bach 6 has a wider cup diameter, the Kelly 5G-EU-SS features a deeper cup.

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

The taper behind the throat leading to the shank. Affects projection and tone character.

Mouthpiece A

Bach 6

• Baritone / Euphonium

Backbore—

Best suited for

📣High-volume projection — open throat for power

Mouthpiece B

Kelly 5G-EU-SS

• Baritone / Euphonium

General

BackboreL

Best suited for

🎻Orchestral playing — large cup for full, dark tone

📋Euphonium general use

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 Bach 6 details Kelly 5G-EU-SS details Bach 6 equivalents Kelly 5G-EU-SS equivalents

Bach 6 vs Kelly 5G-EU-SS

Playing Characteristics

What Do These Model Names Mean?

What Changes If You Switch?

Which is better?

Compare Bach 6 with others

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