Posted by Klaus on December 24, 2001 at 23:35:54:
In Reply to: Re: Odd valve layout posted by Bill B on December 24, 2001 at 23:06:28:
The older makers worked with the S-link to avoid having the "push-rod" (or linkage arm) bumping the mechanism on top of the rotor.
Modern makers work with much more sophisticated alloys. So it might be possible to make crossing linkages, that are bent in 3D patterns and still are stiff and light enough.
Your wish to manipulate the half step valve slide while playing would come frome a wish to play the low B natural and the low E natural in tune. I would say, that on quite a number of tubas (but of course not on mine) the easier way to go would be to pull the 4th slide, as the pullable branches normally are much longer there.