Bach 18 vs Bruno Tilz 304- S 3
The Bach 18 has a wider cup diameter, the Bach 18 has a larger throat opening.
Mouthpiece A
Bach 18
• Baritone / Euphonium
Cup diameter24.20 mm
Cup depthMedium
Rim width—
Throat diameter5.85 mm
Backbore—
Finish—
Material—
Best suited for
High-volume projection — open throat for power
vs
Mouthpiece B
Bruno Tilz 304- S 3
• Baritone / Euphonium
CatalogCup diameter24.00 mm
Cup depthMedium
Rim width—
Throat diameter4.80 mm
Backbore—
Finish—
Material—
Best suited for
High-volume projection — open throat for power
Cup Diameter
The Bach 18 has a cup diameter of 24.20 mm compared to 24.00 mm on the Bruno Tilz 304- S 3 — a difference of +0.20 mm. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a medium cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
The Bach 18 has a wider throat (5.85 mm vs 4.80 mm). 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.