Which has a bigger cup — Bach 1½C or GR Technologies 3M?

The Bach 1½C has a cup diameter of 17.00 mm / 0.6693 in compared to 16.76 mm / 0.6598 in on the GR Technologies 3M — a difference of 0.24 mm / 0.0094 in. A wider cup generally produces a fuller, darker tone but requires more air support.

How does cup depth compare between Bach 1½C and GR Technologies 3M?

Both mouthpieces share a medium cup depth, so the sound character from depth alone will be very similar.

Bach 1½C vs GR Technologies 3M

Name: GR Technologies 3M
Brand: GR Technologies

The Bach 1½C has a wider cup diameter.

Overall Comparison Cup Diameter Cup Depth Rim Width Throat Diameter Backbore Finish Material

The width of the rim surface that contacts the lips. Wider rims improve endurance; narrower rims improve flexibility.

Mouthpiece A

Bach 1½C

• Trumpet

Rim width—

Mouthpiece B

GR Technologies 3M

• Trumpet

Rim width—

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.