Hey, I'm a jazz soloist, and I need a new mouthpiece. I've been using a lousy generic 12C for a while, and its a lot of trouble getting to the higher notes without changing my overture. What's a comapny you would suggest buying a mouthpiece from?

12C is just about as small as a trombone mouthpiece gets. They do have smaller, but the people who use these have no need for a low register. The only thing that's going to improve your high range at this point is to get into a practice room and play lip slurs and long tones.

Also, it's "embouchure", not "overture". Joe Alessi and JJ Johnson have embouchures, Mozart and Beethoven wrote overtures.

crap i knew there was something wrong with that word >_>

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oh, and i'm not really asking about the size and range and stuff, im just looking for a good mouthpiece company that makes more comfortable mouthpieces. i tried my band teacher's mouthpiece and everything was just much more comfortable effortless than my mouthpiece, which is just a cheap store-brand.

Personally, I like Doug Elliott and Greg Black, but those might be too expensive for you right now. Go with a Schilke or Wick. Good quality mouthpieces for a decent price.

And no, I'm not a Bach fan. Too inconsistent with quality control. Also, they've been on strike forever and have been using replacement workers.

i loved my 12C! now I have like 6 1/2 something or other i can't stand it i can't hit high notes at all. but low notes are great XD

Well, if you can't play high notes on a 6.5 AL, then that means that you haven't done your long tones. Listen to Wycliffe Gordon. He plays the Monette equivalent of a 6.5AL (Monette TS-6), and he has an incredible high range.

kengoh
try getting a king 61/2 al-s jettone mouthpiece. king makes good mouth pieces. and jettones are good for higher ranges but be carfull cause they (jettones) can effect your tone some.

6.5 should do the trick. here's the catch, you should be albe to play high on a 12 also!

I use a 12c but i can't remember what other mouthpiece you can use
but since i play euphonium it's hard to remember
i have a mouthpiece that's 12c-45c

I use a 6 1/2 and I have a 3 octave range not including pedal notes- F to F.

I'd recommend an Urbie Green shallow cup.

When looking for a new mouthpiece, just remember one thing. How high you can play on any given piece is NOT important.

Your tone quality, sound production, and personal comfort are all that matters.

Personally, and this is just me, I sound like crap on little mouthpieces. I can hardly get a good sound out of a 12C, and I have a Jet Tone Urbie Green model that also sounds like crap. I can actually play higher with better sound, tone, intonation and comfort with my Dennis Wick 5bs on my small horn. On my big horn, I mainly use a Warburton 7ST, which is a rather large orchestral piece, and I have no problem hitting high F's and G's, and on good days can get up to the double Bb or C.

Pick a mouthpiece that YOU like, that is comfortable for YOUR face and lips, and that YOU can get a good sound and quality tone out of. Once you have your comfy piece, no matter what it is, you can play anything you want with regular work.

I'd like to jump in here and expand a bit on what Erik has said already.
When you play a note... any note.. your lips must vibrate at the correct frequency to get the pitch you want. When we don't have the developed musculature in our embouchure to buzz the pitch we need, we tend to rely on the metal of the mouthpiece to provide that extra support that our muscles should be providing. Changing mouthpieces because your high range isn't good enough is like buying a fancier set of crutches.
The rim size , in my humble opinion should be based on your facial structure, embouchure style and comfort. Cup depth... while the added resistance can make the high range speak a little easier, the depth and shape of the cup should be chosen for the sound it gives. Backbore, same thing. My point is, get the mouthpiece that gives you the SOUND you are after, and build your range accordingly.
Just to give you an example, I play and rim size that is considered fairly large (between a Bach 3 and 4) for all my playing, including lead playing in the US Navy Showband. I provide the range, not the mpc . The shallow cup on the small horn mpc provides the edgier lead sound I need. On my large tenor, I use the same rim, just with a much deeper cup and much bigger backbore. Again, I provide the range. As a matter of fact, my range isn't any different on either horn. I know for a fact that the lead bone player in the Navy Commodores plays lead bone on a 5GS mpc. And believe me, his range is just fine. In a lesson with Doug Elliott, he showed me that he was using a huge mpc rim size even bigger than mine, and his range is amazing.
Another point. Any time you change mouthpieces, you change ever so slightly the muscles you use when you play. Anything different tends to feel and sound great for a while. But sooner or later, the honeymoon will end and reality will set back in.
Bottom line, chose your equipment with the guidance of a good, knowledgeable teacher who can help you decide based on YOUR needs, YOUR facial structure, etc. Strive for great sound. Work your range through long tones, flexiblity exercises, mpc buzzing and free buzzing, Remington range studies, and many others. There are no magic mouthpieces out there that will make you play high. It just takes time and practice.