Additional info on Edgar Villchur mentioned in this thread who invented the worlds first moving piston acoustic suspension speaker in 1952 which allowed lower bass frequencies down to 35hz. His patents were issued up through 1957 but in 1958, his patents were challenged by an electronics company in Federal Court since one of the
parts in the acoustic suspension speaker belonged to this company and was not designed or manufactured by Acoustic Research. Vilchur's patents were denied. He got burned. He got so depressed that he left the speaker business and made a fortune designing and manufacturing hearing aids. His three remaining partner's in Acoustic Research, Kloss, Lowe, and Hoffman, took the first initial of their last names and founded K.L.H.
parts in the acoustic suspension speaker belonged to this company and was not designed or manufactured by Acoustic Research. Vilchur's patents were denied. He got burned. He got so depressed that he left the speaker business and made a fortune designing and manufacturing hearing aids. His three remaining partner's in Acoustic Research, Kloss, Lowe, and Hoffman, took the first initial of their last names and founded K.L.H.