Production Glossary
Stereo Sound
Stereophonic sound, or stereo, is the illusion that sound is advancing from several different audible paths. Stereo sound is commonly referred to as surround sound, a name which helps to describe the way stereophonic sound is perceived by the listener. Stereo sound is produced using more that one audio channel and a system of speakers (at least two). The purpose of stereo sound is to trick the brain into interpreting the individually recorded and designed sounds as a sound that is emanating from a singular source and interpret it as ‘natural’, or as close to reality as the mind can.Stereo sound is comprised of two types of systems: natural stereo and artificial stereo. Natural stereo is produced when a multitude of microphones capture a sound with all its natural vibrations and environmental influences. Once the sound has been recorded, it is played through a number of speakers to simulate the live sound that was captured. Artificial stereo is when a mono sound is duplicated over loudspeaker. As the signal is transmitted, the amplitude is manipulated to create the illusion of directional sound.
The first experiments with stereo sound occurred in 1881 by Parisian Clement Ader using a telephone system. The stereo sound systems known today were patented in the 1930s by an EMI executive, Alan Blumlein. Surround sound moved into movie theaters by the late 1930s, with the feature film, Fantasia, being the first to be released in stereo in 1940. 1957 saw the first “mass-produced stereophonic disc” demonstrated for consumers. Today, most consumer and professional electronics are equipped with stereo sound capabilities.
