i am a bass t-bone player player and i really want advice on mouth pieces.
i like to play very low tones but i cant seem to "belt" them out as people say. and i've been thinking about a plastic mouthpiece too.
anybody wanna give advice to me on mouthpieces to get lower?
and about the plastic?

The generic answer:

I know it might not sound true, but mouthpiece has little to nothing to do with range. When choosing a new mouthpiece, try as many as you can, and choose the one that gives you the best sound and tone quality, NOT the best range.

In the end, the mouthpiece does not create the sound. Your lips and lip muscles, riding on the flow of air out of your lungs, do. So if you switch to a larger piece, your lips still have to do the work to get down there. Practice the fundamentals, and you'll get there. You can put any piece into the horn, but after a week or two of adjusting, your range will return to what it was on the old piece. Only tone and sound quality will change.

Instead of blowing money on a new piece, get a couple books. First, to get comfy in that low register, buy ANY beginning band book (Yamaha, Standards of Excellence, what-have-you) for the TUBA. Work out of it everyday. Also, check out Charles Vernon's book, "A Singing Approach to Playing the Trombone", and Ben van Djik's book, "Ben's Basics".

Once you have gotten down the range you want, then you go for the piece that will give you the sound and tone quality you are looking for.

Now, a couple questions. What mouthpiece and horn are you playing on now? How old are you and how long have you been playing? Why do you want a plastic piece? What kind of bands do you play in? What kind of sound output are you looking for? Orchestral? Big Band? Pop/Commercial?

And of course, MOST importantly, we here can't give definitive answers without actually hearing you play. The BEST thing you can do is to get an experienced teacher, even if just for a few lessons, to listen and critique you and help in your search for new range and new equipment.

Good luck!

well i heard that the plastic is more sticky i guess? to your lips. and i was wondering if the factor of it sticking instead of slipping after playing would help.
i guess i'm just wondering if the plastic gives a better or worse advantage and how?

Have you agree with what Erik said. Really getting low notes to 'pop' as some people put it has very little to do with your mouthpiece. It's all about exercises and how much work you put into it.

If you have a daily warmup routine try adding this in (If you don't have a warmup routine, you need one): Start in 1st position and play the middle F then lip slur up to the high F hitting the Bb and D between. Now do that in 2nd, 3rd, etc. Then play that middle F again and go down to the low F without playing the notes between and really focus on the attack of your low notes. Now do that in 2nd, 3rd, etc. My teacher had me start doing this and I've gone from (With a tenor with F attachment) barely being able to consistently play a low Eb or D to being able to easily belt out that low C and my high notes come out more clear and easier. It also helps increase your upper range some. In higher range I went from being able to being able to play high G pretty consistently and high Ab sometimes to now I can almost always hit high C (4 ledger lines above the staff).

Also do something for a warm down everyday. Not only will it help your endurance in the long term, but it will also prevent you from having noticeable fatigue between playing.

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Forgot to talk about plastic mouthpieces. I've personally never played one but I don't think it's worth wasting the money on. I can't imagine their tone is better than metal, if even equal to metal. The only reason I would ever get one is if you're in a marching band that does a lot of very cold work but even then unless you already have all the fun things like mutes and stuff...suck it up?

Coming from someone who has played out in the cold a LOT.
A plastic mouthpiece can be a life saver. jRent says to suck it up. I say why be any more miserable than you have to be.
A plastic mouthpiece wouldn't really be a good principal mouthpiece though. However, I use Doug Elliott mouthpieces with just the rims that are plastic and I can't imagine playing anything else.

thanks guys, been a super help!!! i ask this cause im going into marching next year and jus wanted a lil advice