Which has a bigger cup — Bach 14½D or Bach 4?

The Bach 4 has a cup diameter of 26.00 mm / 1.0236 in compared to 24.50 mm / 0.9646 in on the Bach 14½D — a difference of 1.50 mm / 0.0591 in. A wider cup generally produces a fuller, darker tone but requires more air support.

How does cup depth compare between Bach 14½D and Bach 4?

The Bach 4 has a medium cup while the Bach 14½D has a shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.

Bach 14½D vs Bach 4

Name: Bach 4
Brand: Bach

The Bach 4 has a wider cup diameter, the Bach 4 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 14½D

• Baritone / Euphonium

Material—

Best suited for

📣High-volume projection — open throat for power

Mouthpiece B

Bach 4

• Baritone / Euphonium

Material—

Best suited for

📣High-volume projection — open throat for power

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.