Posted by Rick Denney on August 29, 2000 at 12:43:13:
In Reply to: Re: Re: Re: Compensating system. posted by Chuck on August 29, 2000 at 11:47:52:
Yes. Stauffer's book has a picture or two of the valves of a compensating rotary Hirsbrunner.
And in about 1985, I play-tested a three-valve (!) Miraphone with compensating valves. It was a standard Blaikley concept, with double rotary valves like a French horn, on a 186 chassis. I found it sitting in a typical suburban music store in Austin, Texas. I don't know how long the store owner had been showing the instrument, but he told me it was a prototype that he had bought from a Miraphone rep. The lacquer was a bit crazed, so I suspect he'd had the horn in his shop for several years at least. Despite my unsophisticated testing, I remember being not much impressed with the horn, and I wondered even then what Miraphone was hoping to accomplish with it, and why they didn't make it a four-valve compensator as long as they were going to the trouble.
On the subject of double tubas, Stauffer's book has pictures of a horn owned at the time (and perhaps still) by Vince Simonetti. It was a York F/BBb, and a true double. It used two coupled rotary change valves, one in the leadpipe, and a huge one in the conical branch downstream from the tuning slide(s). The valves were about a foot long, with the BBb valve branches on the front side and the F branches on the back side (or maybe the other way around. You wouldn't have the problem of excessive cylindrical tubing with that design, but it seems to me that the taper would either have to expand too rapidly approaching the second change valve on the F side or not rapidly enough on the BBb side. (Yes, I know that the same complaint could be made of the Yamaha 621 series--but even in that case I think the F works much better than the BBb on that chassis.)
Rick "Double-talker" Denney