Bach 12C vs Bach 15EW
The Bach 12C has a wider cup diameter.
Mouthpiece A
Bach 12C
• Trombone
Cup diameter24.50 mm / 0.9646 in
Cup depthShallow
Rim width—
Throat diameter5.85 mm / 0.2303 in
Backbore—
Finish—
Material—
Best suited for
High-volume projection — open throat for power
vs
Mouthpiece B
Bach 15EW
• Trombone
Cup diameter24.30 mm / 0.9567 in
Cup depthShallow
Rim width—
Throat diameter5.85 mm / 0.2303 in
Backbore—
Finish—
Material—
Best suited for
High-volume projection — open throat for power
Cup Diameter
The Bach 12C has a cup diameter of 24.50 mm / 0.9646 in compared to 24.30 mm / 0.9567 in on the Bach 15EW — a difference of 0.20 mm / 0.0079 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a shallow cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
Throat diameters are essentially identical at 5.85 mm / 0.2303 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.
Compare Bach 12C with others
Compare Bach 15EW with others
Popular Trombone comparisons
- Bach 12E vs Bob Reeves 5G Gladstone
- Yamaha SL-YEO-S vs Marcinkiewicz ET3C. Loper
- Giardinelli Sym. T vs Bach 12E
- Schilke 45B vs Marcinkiewicz ET3C. Loper
- Denis Wick 6BL vs Conn Connstellation 7CW
- Yamaha SL-48DL vs Yamaha SL-YEO-S
- Conn Connstellation 7CW vs Bach 6½A (small shank)
- Giardinelli Sym. T vs Bruno Tilz 306-5 GS