Re: question about mouthpiece on '36 10M
I have noticed that the more tip opening that is used the sharper the sax will play. It seems to work like a camshaft in an engine, more tip opening works better for the higher register, where less works better for the lower. I think that this is why you are squeaking at the higher end. I own a 10M 275xxx serial, which I believe is a 1937 sax, and the Yamaha 4c mouthpiece is what I use on it.