Posted by Gus Pratt on October 03, 2003 at 09:01:14:
In Reply to: Blaikley 3 valve compensator posted by Did anybody ever on October 02, 2003 at 21:12:53:
I remember seeing photos of a 3 valve compensator with rotors once, that I think Hirsbrunner made for the Swiss Army. If I recall there was a photo in Treatise on the Tuba. I don't if any other manufacturers made any. The problem you have is that the compensating system was under patent protection until about the mid 70s so that only Boosey and Hawkes/Besson was able to manufacture any compensators.