Posted by Matt on December 06, 1999 at 00:41:22:
This has probably been discussed before, but what distinguishes the Rotax rotors on the Willson/Kurath instruments from other rotors. The only thing that I ever read is that they have 100% geometrical volume, and on the Willson Bass Trombone they are supposed to be equal to a Thayer valve (little/no difference from open). But does anyone with the knowledge, and/or a Willson instrument, know how these valves are constructed? I imagine their introduction to the market was before my time since there is little talk of them anymore.
Thanks,
Matt