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

Base metal or construction (e.g. brass, stainless steel, plastic). Influences weight, response, and tone color.

Mouthpiece A

Bach 3C

• Trumpet

Material—

Best suited for

🎵All-round versatile — balanced cup for general playing

Mouthpiece B

GR Technologies 3M

• Trumpet

Material—

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.