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

The GR Technologies 3M has a cup diameter of 16.76 mm / 0.6598 in compared to 16.30 mm / 0.6417 in on the Bach 3C — a difference of 0.46 mm / 0.0181 in. A wider cup generally produces a fuller, darker tone but requires more air support.

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

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

Bach 3C vs GR Technologies 3M

Name: GR Technologies 3M
Brand: GR Technologies

The GR Technologies 3M 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 3C

• Trumpet

Rim width—

Best suited for

🎵All-round versatile — balanced cup for general playing

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.