Posted by Chuck(G) on September 18, 2001 at 11:29:57:
In Reply to: Re: Re: Re: Re: Re: Thayers on tubas.... posted by Klaus on September 18, 2001 at 11:00:36:
(Standard disclaimer; I am not a trombonist)
As I understand it:
The Greenhoe valve is made oversized relative to standard rotary valve, and instead of having the airways milled into the side of the rotor, has them milled as complete round sections through the rotor. My assessment is that this preserves the overall shape of the tube and makes for less leakiness.
Having said all that, the Greenhoe is a minor improvement to a standard rotary valve at the price of a larger footprint. But not as large as a Thayer.
But then the subject of the original post was Thayer valves and their suitability for tubas. If we are taking trombone innovations and applying them to tubas, then the Greenhoe valve may be the most reasonable. Indeed, one of the news releases says that Greenhoe is working on a valve for tuba application.