does anybody know what the range is for alto trombone i play tenor trombone and would like to try and play the alto trombone

Like any brass instrument, the range of the alto trombone will vary depending on the player and if you have a Bb attachment on the horn.
Generally speaking, if you can't play it on a tenor, you probably won't be able to play it on the alto. Keep in mind you still have to be able to buzz the pitch you want.
That said, certain notes will just jump out of the alto that may have sounded more strained on the tenor. The added resistance will also help with some endurance issues. However, alto is generally chosen for it's brilliant tone and how it works within the piece of music and the ensemble more than because what you are playing is high.
This past year at the Eastern Trombone Workshop, the Philidelphia Orchestra's low brass section did something very cool where they played Beethoven's 9th twice... once with Nitzan Haroz playing the first part on tenor, and once with Matt Vaughan playing it on alto. It was really cool to get to hear the difference side by side like that. Same piece, two different voices.
If you want to hear some cool alto trombone action, check out the CD 'Four of a Kind 2' and hear the Overture to Barber of Seville, which features Joe Alessi and Mark Lawrence both playing altos.
How long have you been playing trombone? Will you have the guidance of a teacher when if and when you add alto into your practice?

i was just thinking about that too. i imagan you can play just as low as a tenor(stright horn) too;maby not with as good of a tone but i could be wrong. i was thinking about bying an alto. i love how they sound. i could use it for a trombone quire we're going to play this year

Steve, have you heard the Carmen Fantasy on Joe Alessi's album, "Trombonastics"? Alessi uses the alto for the last movement, and it is absolutely incredible. He makes it sound easy.

And I don't know if you've heard his newer album of Italian songs on the Naxos label. He plays an arrangement of Barber of Seville for alto trombone and piano, and it's quite amazing what he does on that too. I even heard him do that arrangement live about three years ago when he did a masterclass at a local high school.

I haven't heard Alessi's solo version of Barber of Saville, but I have heard Lindberg do it. I'll check out the other recordings you mentioned. Thanks for the recommendations.
Bob, here's a question for you... in light of this topic, when do you feel is a good time for a player to begin working on an alto? I'm speaking in genralities here, just for discussion purposes.

I think that they have to have solid command of the tenor tromobone before starting on alto. I don't have any idea of grade levels of solos, but they have to be proficient enough to play a piece like the Rimksy Korsakov concerto or David Concertino. And since the alto trombone has a much smaller bore than an orchestral tenor, the student will have to learn how to adjust his airflow in order to play the alto correctly.

This is why I love Doug Elliott mouthpieces so much. I can use the same rim on both my orchestral horn and my jazz horn.

Sam Burtis has said that when doubling on two different types of trombones, practice an equal amount of time on both of them, and do the same exercises as well. This I know for a fact: I had been playing my jazz tenor exclusively for about a month straight. Then I was asked to sit in a big band on bass bone, and the bass felt so foreign to me. It took a few days of practicing the bass until it felt normal again, so that I was getting the tone quality and articulations that I desired.

Yeah, switching can be a pain, that's for sure. Lately, I've been playing quite of bit of tenor, alto, and bass. Sam also uses as system of "primary horn of the day". Personally, I can't spend equal time every day, so I base my routine on what the demands of the next few days will be.
As for when to start... I agree with you that you should have a good command of the instrument first. I just get concerned when some players want to start it too soon, and also for the wrong reasons.

i think that i still have alot of work do on my tenor trombone maybe i will try alto in a year thank you verry much for the comments