New York Bach Cup Sizes

[rabiddolphin]

I've been trying out some different mouthpieces on one of my horns and I wound up using a 9A, does anyone know of an old Bach catalog I could look into to find out more info on this mouthpiece?

[SteveM]

Chances are there is no difference. The 9 is an A cup mouthpiece, they just didn't (usually) specify the "A" in the model number, for unknown reasons.