Lexicon DC-1 Supplementary Manual page 24

DC-1 Theory
and Design
DC-1 Digital Controller
The Party effect is provided to allow music to be played over your entire
system. All speaker outputs in this mode are simply fed a stereo signal. The
left front and left side speakers are driven by the left input signal. The right
front and right side speakers are driven by the right input signal. The center
and rear channels are both driven by the sum of the left and right inputs. A
High Pass parameter allows you to remove bass from side and rear speakers
which might not be able to handle it. Center Level and Subwoofer Level
controls are also provided. This effect is primarily useful for large audi-
ences, or background music when entertaining.
Film Surround
The goal of the DC-1 film surround effects is to maximize viewer involve-
ment and to faithfully reproduce the director's intentions for the soundtrack
in your own listening environment. Before explaining the way each of the
film surround effects (Mono Logic, Pro Logic, THX Cinema, TV Matrix, and
Logic 7) 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 the-
ater 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.
As a result, sound technology in theaters froze. 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.
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