Which has a bigger cup — Bach 17C or Bach 18?

Both mouthpieces have virtually identical cup diameters at 15.10 mm / 0.5945 in.

How does cup depth compare between Bach 17C and Bach 18?

The Bach 18 has a very deep cup while the Bach 17C has a medium cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.

Bach 17C vs Bach 18

Name: Bach 18
Brand: Bach

the Bach 18 features a deeper cup.

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 17C

• Cornet

Material—

Mouthpiece B

Bach 18

• Cornet

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.