41. A Quadraphonic mix was available on both vinyl and Quadraphonic 8-track tape formats. 42. He was the inventor of the QSI system that sparked up interest in quadraphonic broadcasting. 43. The album was a standard recording but available in two formats : quadraphonic and stereo. 44. Two decades ago, the recording industry brought forth a flashy surround technology dubbed quadraphonic sound. 45. A Quadraphonic mix of the album was available in the Quadraphonic 8-Track cartridge format. 46. A Quadraphonic mix of the album was available in the Quadraphonic 8-Track cartridge format. 47. A Quadraphonic mix of the album was available on the Quadraphonic 8-Track cartridge format. 48. A Quadraphonic mix of the album was available on the Quadraphonic 8-Track cartridge format. 49. A 8-track cartridge formats, and is considered one of the rarest quadraphonic releases. 50. Pfeiffer helped RCA develop stereo and quadraphonic recording techniques and coordinate their adoption of digital recording.
