TubeNet

Pictures up:

http://thevillagetinker.com/Holton%20SA ... aphone.htm

The horn plays very well. Some have reported that these old horns were 'stuffy'. That's not my experience... at least no more 'stuffy' than any other sousa I've played! However... there is an incredible amount of 'bell ring' one some notes. That's easily taken care of with some split vinyl tubing around the rim.

KiltieTuba wrote:How does this compare to the Conn 20K's short action valves?

They are a bit "faster" due to less mass in the piston. The biggest issue about these valves is the difficulty in tubing layout, and they seem to be prone to leakage due to the large amount of surface area involved.

Matthew Gilchrest wrote:

KiltieTuba wrote:How does this compare to the Conn 20K's short action valves?

They are a bit "faster" due to less mass in the piston. The biggest issue about these valves is the difficulty in tubing layout, and they seem to be prone to leakage due to the large amount of surface area involved.

Yeah... what he says. There is a LOT of linear seal area on the perimeter of the ports... much more than on a 20K or other tubas/sousas. The pistons have to be fit very well to enable a good seal. Another thing is that the port alignment is critical. The edges of the ports need to be sharp. Rather than the open bugle just passing through the valve section with a few little squiggles.... the open bugle involves the sound waves moving into the first piston, out, and 180 degrees around to the 2nd piston, in, out and another 180 degrees to the 3rd piston. The sound makes a lot more turns than through a conventional valve section.