There are a number of things about the soprano saxophone mouthpiece that can effect pitch, and either help you or get in the way. Here are a few things I’ve learned from some of the experts.
Dave Kessler talks about the soprano mouthpiece and pitch on his store website, (see bottom of the page – General Advice…) specifically about mouthpiece placement. The general idea is that for the most part, the mouthpiece should be pushed down quite far on the cork, to where the low register can be played easily in tune, and the upper register can be played in tune without pinching too much.
I have found that when I’m just warming up, my pitch is best with the mouthpiece all the way down. Then, once I’ve warmed up, I pull it up just a bit, maybe ¼”, to get my ideal placement. I think the need to move it slightly is probably a combination of the horn warming up, and my embouchure tightening up to my normal playing state. Or it could be that I’d be better off leaving it where it is, and not tightening up so much! It’s a work in progress.
It should be obvious, but worth mentioning that not all mouthpieces are the same size and shape, so that the placement may vary somewhat. For example, my Soprano Planet OS2 has a shorter shank than my Selmer Soloist, so it doesn’t go down quite as far on the cork.
Speaking of Soprano Planet, Joe Giardullo has a lot to say about soprano mouthpieces, problems associated with them, and fixing them. He’s highly knowledgeable, and persuasive!