User manual LEXICON CP-3 PLUS THEORY AND DESIGN REV 2

[. . . ] CP-3PLUS Theory and Design Lexicon Acknowledgements The CP-3PLUS is manufactured under license from Dolby Laboratories Licensing Corporation. Additionally licensed under one or more of the following patents: U. S. numbers 3, 632, 886, 3, 746, 792 and 3, 959, 590; Canadian numbers 1, 004, 603 and 1, 037, 877. "Dolby" and the doubleD symbol are trademarks of Dolby Laboratories Licensing Corporation. [. . . ] Before explaining the way each of the film surround modes (Mono Logic, Pro Logic and Home THX Cinema) accomplish this goal, it is important to understand something about the way film soundtracks are made and presented in the theater. In the early 1940's, large movie studios owned their own theaters and took responsibility for their own quality standards. During this period, movie theaters had the best sound reproduction heard anywhere -- each major studio had a master sound engineer to ensure that the sound systems in that studio's theaters performed properly. A decade later, the studios were forced to sell off their theater holdings in an anti-trust action, and quality became the responsibility of independent theater owners. Since each theater could choose films from any studio, it was no longer practical, or feasible, for the studios to monitor the quality of each theater. At the same time, the impact of television caused a decline in theater attendance which left little money for individual theater owners to reinvest in their facilities. Despite the advances being made in recording and in home music systems during this period, film sound remained essentially unchanged through the 50's and 60's -- in fact, by the end of the 1960's the average teenager had a music system at home which was considerably superior to theater systems. This situation began to change in the 1970's with the introduction of Dolby Stereo. This technological breakthrough, which allowed four channels of sound to be recorded onto the two available optical soundtracks of a 35mm movie print, yielded spectacular results -- and created a demand for improved film sound tracks, and for better-sounding theaters. Theaters that upgraded their sound systems were rewarded with larger audiences. Over the next decade, Dolby Stereo became an established standard for film sound recording -- but theater sound systems, although improved, varied in their ultimate accuracy. In the 1980's a new movie theater sound system was created under the name THX. This system addressed, for the first time, the design of a theater speaker system which could faithfully reproduce the film director's intentions. The THX Sound System complemented and enhanced the playback of Dolby Stereo, and encompassed standards for power amplifiers, speakers, and the acoustics of theaters themselves, to assure the best possible reproduction of movie soundtracks. By 1990, this system was available in over 500 theaters across the country. The recent availability of film on video tape has led to a demand for home audio/video systems which equal the best theater sound. The Home THX Cinema system was designed to address this need, and the CP-3PLUS incorporates it into the THX mode. The variety of CP-3PLUS surround film modes allows you to have the highest possible sound quality for video material -- whether you select classic monaural movies or the latest releases with all of their special effects -- simply by changing modes. 16 CP-3PLUS Digital Surround Processor CP-3PLUS Theory and Design Mono Logic Mono Logic is a surround conversion mode for monaural film sound tracks. A quick look through any video rental selection will prove the usefulness of such a mode; a large percentage of titles are mono. One time-honored solution is to break the incoming signal into frequency bands, sending some to one channel and the rest to the other. When the filters are complementary (when the sum of the two output channels equals the original input channel) this solution can give stereo spread without ruining the tonal balance. When the filters are non-complementary, they can produce an unpleasant fake stereo effect. [. . . ] Lastly, hold the Back BALANCE button down to move the balance all the way to the back. It should sound like you are standing in the lobby of the hall with the doors closed. Slowly move the balance to the front of the hall one step at a time by repeatedly pressing Front BALANCE. (Don't hold it down. ) You are now walking down the aisle to take your seat. [. . . ]