TubeNet

Well Doc,

by no means am I an experienced repair guy. One time I cut a Bb trumpet down to Eb. Not for any certain reason, I just did it because i was bored and the horn was there. I did the physics part and firgued out how much I needed to cut. After I cut everything the right length and put it back together, it had the most horrible tuning issues of any horn *ever*.

I think I it was because it was such a drastic cut and i couldn't make it as conical as it needed to be (but Mark, trumpets are cylidrical. Well take off the lead pipe. There is a certain amount of conicalness in a trumpet).

I think BBb to CC is ok. BBb to Eb just might be a little too much. Anyways. good luck my friend.

Mark

Hmmm.... You're gonna have to cut all three of the existing valve circuits and figure out a way to get rid of 4 1/2 feet out of the open bugle. Plus... the chore of adding the 4th valve. Sell it and buy yourself the 4V Eb horn you really want!

It looks very much like a Conn 10J I once had.

To answer your question: The last time I looked (3 years ago) you could get a really good front-action four-piston valve set with associated tubing from Germany for somewhere between $1500 and $2000. Matt Walters at Dillon could probably help you find what you need. If your tuba has good intonation now it will be a dream with a new valve set. If it's similar to a 10J then I would suggest cutting it to CC. It's expensive, but not as costly as a complete new tuba if you do the work yourself. And you get to set it up exactly the way you want it. But if the tuba has intonation issues then don't spend the money because they won't go away. Use Bloke's good advice instead.
-Art-
http://www.galvanizedjazz.com/tuba.html