Posted by Klaus on August 17, 2001 at 14:51:19:
In Reply to: Re: Re: Re: valve extensions or other remedies posted by Mark F. on August 17, 2001 at 14:22:37:
Yes. And at least those I have seen illustrated actually were top valved rotary instruments.
If finger movements are transmitted through spatulas, these latter ones have to be hinged. Invariably leading to a circular movements. Which are very complicated to translate to the straight up-and-down movement needed for piston movements without to applying the lateral powers leading to excessive wear.
From car and ships engines one can learn, that it actually is easier to translate straight movements into rotation. But it often takes a lot of compensatory, and heavy, add-ons to limit wear.
Even in an age, where the design and construction of lightweight and efficient car engines are high up on the political agendas of enviromental conservation, one has to realise, that there are some weight limits reducing the number of options for compensatory mechanical add-on on tubas. And I am specifically not speaking of the more or less welknown compensating tubas.
Klaus