I play a Yamaha 16C4 and a Bach 1.5C and they feel very simular accept I get a clearer tone with the 16C4. My question is about Bach mouthpieces. As I read about inner rim sizes I see that a 1C, 1.25C, and a 1.5C all have the same inner rim and cup size. I know that there must be a difference, what is it?

Check out the website Tom..http://www.selmer.com/products/accessories/mouthpiece/mouth1.html ......I`m sure this information will answer all your questions