Bach 16 vs Kelly 31

The Kelly 31 has a wider cup diameter, the Kelly 31 features a deeper cup, the Bach 16 has a larger throat opening.

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
    Bach 16
    • French Horn
    Throat diameter4.50 mm / 0.1772 in
    Best suited for
    📣High-volume projection — open throat for power
    vs
    Mouthpiece B
      Kelly 31
      • French Horn
      General
      Throat diameter3.80 mm / 0.1496 in
      Best suited for
      🎻Orchestral playing — large cup for full, dark tone
      📣High-volume projection — open throat for power
      📋French horn deep cup

      Throat Diameter

      The Bach 16 has a wider throat (4.50 mm / 0.1772 in vs 3.80 mm / 0.1496 in). A wider throat allows more air through, increasing volume and projection but reducing resistance.

      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 16 details Kelly 31 details Bach 16 equivalents Kelly 31 equivalents