TubeNet

I believe that Doug Yeo had a Bach 50 bell and double slide at one time that was used as a contrabass trombone. If I remember correctly, it was a straight bell. (no trigger assembly). A picture was on his website as well. No playing experience on one except for the Mirafone.

Tom Mason

Actually, since the amount of slide extension is geometric and progressive as you go down in pitch, and not linear, you may not have as many slide positions.

If a Bb horn is @ 9 feet long, then 9 X 2^5/12 to get to F is @ 12 feet, or about 3 feet of extension, give or take, to get to 6th position. But if you're already down in F, which is that same 12 feet of tubing, then 12 X 2^5/12, which gives you the equivalence of F to C, the same perfect 4th down, or sixth position, is longer: 16 feet, which is about 4 feet of extension, and you run out of slide.

It's the same thing as when you trigger a "normal" F-attachment bone: the slide positions are longer, so that you only get about 6 usable positions with the trigger on, rather than 7 for a straight bone. There just isn't enough slide to go progressively lower without coming off the end of the socks.

Now, that said, the slide to get the B nat to F glissando has to be longer than just the F attachment length, or there simply is not enough tubing to get there. That's probably why they caution against trying to use it for anything else: the loop length is an odd length to start with, and that is compounded by the progressive nature of semitones to the octave, which doubles in length each time.

Here's a link on that subject on tromboneforum, see Gabe Langfur's reply on Shires. Maybe you've seen it.

http://tromboneforum.org/index.php/topic,24416.0.html" target="_blank" target="_blank

Tom Mason wrote:I believe that Doug Yeo had a Bach 50 bell and double slide at one time that was used as a contrabass trombone. If I remember correctly, it was a straight bell.

I'd think this instrument would be obscenely out of tune, as it wouldn't follow the usual cylindrical brass formula of "1/3 conical and 2/3 cylindrical".

Of course being a trombone, it's eminently tuneable though.

And of course, being played by a trombonist, it'd still be out of tune.