Alright, I have played trumpet for 7 years now. Now I am in high school and I don't want to use my professional cornet on the field. My band director said I should play Mellophone(sp?), but I really want to play baritone. My director said I could lose my embouchure if I played baritone. I was looking around the net and found an attachment that makes a trombone mouthpiece work in a baritone, so I was wondering what is the closest size trombone mouthpiece to a trumpet mouthpiece? I would say probably 7C since I'd just be starting baritone and I'd imagine that the amount of air that needs to be put through is different. Could anybody please help me on this problem? Thanks!

You could play mellophone using a mouthpiece with a very similar internal rim diameter and play trumpet with the same embouchure. But it would need to be "no pressure" french horn embouchure and the shape of the rim would feel different as would the resistance.

You wouldn't get the expected tone from a baritone if you used a trumpet mouthpiece with a custom adaptor. Playing baritone, euphonium or trombone needs alot of air support (ie fast flowing air) in the high register.

If you were to continue playing trumpet very regularly then learning/playing any other brass instrument wouldn't be a real problem provided you took care not to stress your lips.

I say go with the mellophone. It's pretty close to a trumpet if you ask me (I've only played a mellophone a bit for stuff like pep band during basketball games, but they look really similar). The mouthpiece, as far as I can tell, is exactly the same as trumpet, so your embouchure wouldn't be affected much. I don't know about air support though...

This last marching band season (I played trumpet for marching band), during one practice, I picked up one of my friend's mellophones, stuck my mouthpiece in it, and played it a bit. It wasn't hard at all, it just came naturally, especially the fingerings .

Being a baritone player and conisuer of various brass instruments, i would say that the best medium for your instrumental switch-over would be a , fluegalhorn, most band directors of any merrit have one lying around somewhere, "just-in-case".

The beauty of a fluegalhorn is that it plays the same as a T.C. Baritone but can accept nearly any brass mouthpiece, including trumpet, cornet, french horn, and trombone, but i've found that euphonium mouthpieces work the best. I'm not entirely sure, but I believe a flugalhorn's closest relative is a cornet, the difference being that a cornet is more tubular, whereas a fluegalhorn is conical (essentialy the same difference between a baritone horn and a euphonium), so as a crossover from cornet, that would be my recomendation for feild and marching work.