Bach 1B vs Bob Reeves 43.5/ES/s
The Bob Reeves 43.5/ES/s has a wider cup diameter, the Bach 1B features a deeper cup.
Mouthpiece A
Bach 1B
• Cornet
Cup diameter17.00 mm / 0.6693 in
Cup depthDeep
Rim width—
Throat diameter3.66 mm / 0.1441 in
Backbore—
Finish—
Material—
Best suited for
Orchestral playing — large cup for full, dark tone
vs
Mouthpiece B
Bob Reeves 43.5/ES/s
• Cornet
Cup diameter17.26 mm / 0.6795 in
Cup depthVery shallow
Rim width—
Throat diameter—
Backbores
Finish—
Material—
Cup Diameter
The Bob Reeves 43.5/ES/s has a cup diameter of 17.26 mm / 0.6795 in compared to 17.00 mm / 0.6693 in on the Bach 1B — a difference of 0.26 mm / 0.0102 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Bach 1B has a deep cup while the Bob Reeves 43.5/ES/s has a very shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
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.