TubeNet

http://tinyurl.com/2tzr5l

This is an interesting concept...does anyone know if this kind of thing exists for tuba?

I know Jacobs had some made for him (Schilke?), but does someone know if anyone has these in production?

Yes, several makers have offered them for tuba (and trumpet and trombone). I think you can still get Gerry Endsley in Denver to make you one.

They don't work the way you think they ought to (Owned one, sold it).

Consider that to get these things to work, you have what's essentially a piston working in a cylinder--when it's set shallow, you can get along pretty well, but when you set it deep, you've got a straight-sided cylinder ending in a relatively flat-faced surface. The resulting shape isn't a funnel or a cup--it's a cylinder.

Generally, most folks who own these will tell you that they work acceptably well in one or perhaps two positions.

Just not worth the expense for an at best, passable, mouthpiece. Otherwise, everyone would have one.

I can't wait for the Chinese manufacturers to start offering them.