Bach 1½C vs Kelly 4B-UK

The Bach 1½C has a wider cup diameter, the Kelly 4B-UK features a deeper cup, the Kelly 4B-UK has a larger throat opening.

Overall Comparison Cup Diameter Cup Depth Rim Width Throat Diameter Backbore Finish Material
How deep the cup is, from shallow (brighter, easier high register) to deep (darker, fuller sound).
Mouthpiece A
    Bach 1½C
    • Cornet
    Cup depthMedium
    vs
    Mouthpiece B
      Kelly 4B-UK
      • Cornet
      Orchestral
      Cup depth
      Best suited for
      📣High-volume projection — open throat for power
      📋Professional cornet; British brass band

      Cup Depth

      The Kelly 4B-UK has a — cup while the Bach 1½C has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.

      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 1½C details Kelly 4B-UK details Bach 1½C equivalents Kelly 4B-UK equivalents