Ultra Stereo is a cinema sound system that was developed in 1984[1] by chief engineer Jack Cashin.
Ultra Stereo Labs (USL), which had been concentrating on the manufacture of sound equipment for studio screening rooms, was drawn into the exhibition-end of the business.
Specifically, the USL cinema processor achieved greater channel separation than had been possible up to that time.
[3] The Ultra Stereo JS series model 105/195 unit introduced a six channel discrete input module (JFM-20 SR) circa 1993 which creates a THX approved 5.1 surround field.
When the industry moved away from analog soundtracks, USL transitioned to digital processing in all their audio products.