DTS

Digital Theater Systems, Inc., based in Agoura Hills, CA, owns DTS®, a multi-channel digital surround sound format used for both commercial/theatrical and consumer grade applications. It is used for film, DVD, and Blu-ray® discs.

Work on the format started in 1991, with film director Steven Spielberg as one of the company's initial investors, who felt that optical theatrical sound formats had become obsolete. The first release was Spielberg's 1993 Jurassic Park. DTS's major competitors in multi-channel theatrical audio are Dolby Digital and SDDS®, although only Dolby Digital and DTS are implemented in home theater hardware since SDDS® is a theatrical-only format.

In the consumer home theater market, DTS offers several options for multi-channel playback, usually encoded at a higher bit rate than allowed for by Dolby Digital AC-3, including DTS-ES, DTS-NEO:6, DTS-HD, and DTS-HD Master Audio. The basic and most common version of the format is a 5.1 channel system similar to a Dolby® Digital setup, which encodes audio as five full-frequency channels plus a special LFE (low frequency effect) channel for the subwoofer.

How does DTS work theatrically? Information in the form of a modified time code is optically imaged onto the film (see illustration for location). An optical LED reader reads the time code data off the film and sends it to a DTS processor that uses it to synchronize the projected image with the soundtrack audio that has been recoded in compressed form on standard DCD-ROM optical disc media at a bit rate of 1103 kbps.

By comparison, DTS's main competitor, Dolby Digital's audio is placed between the sprocket holes of projected film, leaving the content susceptible to physical damage due to film wear and mishandling. Whereas Dolby Digital and SDDS audio reside on the actual film, DTS's audio is on the optical disc, eliminating the possibility of damage through wear except in cases where the film’s time code track is completely destroyed. In a way, this technology hearkens back to the Vitaphone process, the most successful of the original sound-on-disc formats.

This article is licensed under the GNU Free Documentation License found at http://www.gnu.org/copyleft/fdl.html. It uses material from the Wikipedia article at http://en.wikipedia.org/wiki/DTS_(sound_system).

The DTS time code track is highlighted in red in this illustration.

Macro of 35mm film audio tracks, from left to right: Sony SDDS, Dolby® Digital, analog Optical, and DTS time code. Image courtesy of Wikipedia Commons.