Bach 12E vs Bruno Tilz 305-D 1
the Bach 12E has a larger throat opening.
The internal diameter of the cup, measured at the widest point inside the rim.
Mouthpiece A
Bach 12E
• Trombone
Cup diameter24.50 mm / 0.9646 in
Best suited for
High-volume projection — open throat for power
vs
Mouthpiece B
Bruno Tilz 305-D 1
• Trombone
CatalogCup diameter24.50 mm / 0.9646 in
Best suited for
High-volume projection — open throat for power
Cup Diameter
Both mouthpieces have virtually identical cup diameters at 24.50 mm / 0.9646 in.
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.