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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.
During the 1980's, the film industry experienced a kind of renaissance, and the introduction of home video technology and widespread cable access created a means for people to watch movies they had seen in the theater in their own home. During this same time period, Dolby Laboratories created a Dolby processor to read the new Dolby stereo optical format. These events led to both the interest in theater-quality sound for the home and the ability to provide it at reasonable cost.
In late 1982, Dolby Surround was introduced for playing video of theatrical films originally produced with Dolby encoded soundtracks. After a while, Dolby Surround Pro Logic decoders made it possible to decode the center channel as well.
During the late 1980's, Dolby Laboratories switched to applying digital audio technology to 35 mm film. In order to encode Dolby Digital in film, the optical track was placed between the sprocket holes. This is when the "5.1" configuration made its appearance in surround sound. The 5.1 configuration has five full-range channels -- left, center, right, left surround and right surround. There is also a sixth channel for powerful low-frequency effects (LFE) that are felt more than heard in cinemas. Because the LFE channel only needs about one-tenth the bandwidth of the others, it is referred to as ".1" channel. The Dolby Digital format was introduced to theaters in 1992 and continues to be the leading digital format. The trend has now moved to home theater systems.
DTS, short for Digital Theater System, was founded in 1990 by Terry Beard and funded by Universal Studios. DTS introduced its sound with the release of Steven Spielberg's blockbuster Jurassic Park. In six months, DTS was able to install 876 DTS playback systems in theaters. Every major film studio in the U.S. uses DTS multi-channel digital sound and all soundtracks in the DTS format.
In 1996, DTS Coherent Acoustics was developed and is now widely used in home theater and car audio, video games, DVD-Video, 5.1 Music discs and DVD-Audio and PC. DTS is supported by every major consumer electronics manufacturer worldwide, more than 70 million homes; auto and portable entertainment products now include DTS trademarks or technology. |
