quadriphonics

/ˌkwɑdrəˈfɑnɪks/
noun
  1. The technology or field of sound recording and reproduction using four separate channels.
    • Quadriphonics was a popular innovation in audio technology during the 1970s.
    • The engineer specialized in quadriphonics and helped design early surround-sound systems.
    • Many modern home theater systems owe a debt to the experiments in quadriphonics.