Surround sound was first developed in the 1950's for cinema, using a minimum of four channels. Cinemas were equipped with additional amplifiers and speaker systems. Most theaters featured several channels across the front, plus at least one channel towards the rear, which became known as the effects channel and was reserved for the occasional dramatic effect.
In contrast, home sound systems (stereo) used a two-channel format, because that is all the LP phonograph record could accommodate. Because of this, the average consumer only knew stereo as a two-channel format, and only film buffs were aware that film stereo used more than two channels. Until the mid-1980's, home stereo sound, cinema stereo sound, and TV sound were different systems supported by essentially isolated industries.
Events beginning in the 1980's created new cinema sound systems, and created both the market for and the capability to provide theater-quality sound in the home.
