Something my director told me a while ago hit me with an idea: He was talking about a tuba mouthpiece, and how a tuba player can hit a trumpet register (so to speak) by accustoming himself to a trumpet mouthpiece (a trumpet embouchure) and using this trumpet embouchure in the tuba mouthpiece. (We were talking about pedal tones) He then said that to do the reverse (take the tuba embouchure to the trumpet mouthpiece) is harder, for the trumpet mouthpiece has no extra space to place that embouchure. My idea is about different sized mouthpieces to develop the different ranges more (I am young, and I'm sure many of you have noticed that I talk about developing things). I use a Bach 1C mouthpiece regularly, and it is fabulous. I just stuck a 12 C mouthpiece in the trumpet (like a wall with a hole in it ) and my embouchure fit itself to that mouthpiece, where the higher register came much more effortlessly (and was wider, as you can imagine). How would it be if I were to help out my register by getting a tighter embouchure with the 12 C (or something less drastic, like a 5C (or even the 3C has a difference)) while still dutifully relying on the 1 C for the final product (and everyday playing, of course)? Asking especially those who have experience experimenting with different mouthpiece sizes.