Bach 6½AL (large shank) vs Bach Mega Tone Trombone 6½AM
the Bach 6½AL (large shank) has a larger throat opening.
Mouthpiece A
Bach 6½AL (large shank)
• Trombone
Cup diameter25.40 mm / 1.0000 in
Cup depthDeep
Rim width—
Throat diameter6.63 mm / 0.2610 in
Backbore—
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
High-volume projection — open throat for power
vs
Mouthpiece B
Bach Mega Tone Trombone 6½AM
• Trombone
Cup diameter25.40 mm / 1.0000 in
Cup depthDeep
Rim width—
Throat diameter6.53 mm / 0.2571 in
Backbore—
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 25.40 mm / 1.0000 in.
Cup Depth
Both mouthpieces share a deep cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
The Bach 6½AL (large shank) has a wider throat (6.63 mm / 0.2610 in vs 6.53 mm / 0.2571 in). 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.