Bach 12 vs Schilke 69C4
the Schilke 69C4 features a deeper cup.
Mouthpiece A
Bach 12
• Tuba
Cup diameter32.75 mm / 1.2894 in
Cup depthMedium
Rim width—
Throat diameter8.33 mm / 0.3280 in
Backbore—
Finish—
Material—
Best suited for
High-volume projection — open throat for power
vs
Mouthpiece B
Schilke 69C4
• Tuba
Cup diameter32.76 mm / 1.2898 in
Cup depthDeep
Rim width—
Throat diameter8.33 mm / 0.3280 in
Backbore21/64.3281"
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
Cup Diameter
Both mouthpieces have virtually identical cup diameters at 32.75 mm / 1.2894 in.
Cup Depth
The Schilke 69C4 has a deep cup while the Bach 12 has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
Throat diameters are essentially identical at 8.33 mm / 0.3280 in, so resistance feel will be comparable.
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.