Giardinelli 5D vs Kelly 5G-EU-SS

The Kelly 5G-EU-SS 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
Mouthpiece A
    Giardinelli 5D
    • Baritone / Euphonium
    Cup diameter25.00 mm / 0.9843 in
    Cup depthDeep
    Rim width
    Throat diameter6.00 mm / 0.2362 in
    Backbore15/64" (.234)
    Finish
    Material
    Best suited for
    🎻Orchestral playing — large cup for full, dark tone
    📣High-volume projection — open throat for power
    vs
    Mouthpiece B
      Kelly 5G-EU-SS
      • Baritone / Euphonium
      General
      Cup diameter25.40 mm / 1.0000 in
      Cup depth
      Rim width
      Throat diameter
      BackboreL
      Finish
      Material316 Surgical Stainless Steel
      Best suited for
      🎻Orchestral playing — large cup for full, dark tone
      📋Euphonium general use

      Cup Diameter

      The Kelly 5G-EU-SS has a cup diameter of 25.40 mm / 1.0000 in compared to 25.00 mm / 0.9843 in on the Giardinelli 5D — a difference of 0.40 mm / 0.0157 in. A wider cup generally produces a fuller, darker tone but requires more air support.

      Cup Depth

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

      Material

      The Giardinelli 5D is described as unspecified, and the Kelly 5G-EU-SS as 316 Surgical Stainless Steel. Material affects mass, warmth, and how quickly the piece responds.

      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 5D details Kelly 5G-EU-SS details Giardinelli 5D equivalents Kelly 5G-EU-SS equivalents