Lexicon CP-1 Theory Of Operation page 4

Multi-Channel Music & Cinema Systems
Theory and Design
Introduction
All of the Lexicon home theater surround sound processors have a common
goal: to draw you, the listener, more deeply into a musical performance or
a film. For music, we use true stereo digital processing to recreate the
original recording space or to create a new one of your choosing. For films
we incorporate discrete digital multi-channel surround processing for both
Dolby Digital (AC-3) and Digital Theater Systems (DTS) formats. For two
channel surround encoded films we include our own proprietary 5 and 7
channel implementations of the original Dolby Pro Logic surround decoder.
These improvements yield a greatly increased sense of surround and
envelopment, as well as spectacular left/right surround effects.
Our processors are flexible enough to satisfy the most critical listeners and
yet simple to operate. Essentially, they are signal processing computers that
can be custom-programmed for any specific system. The increase in impact
of a musical performance or film when heard with Lexicon processing is
incredible.
To recreate the experience of being at a live musical performance we have
drawn on recent studies of concert-hall acoustics, and applied this research
to home listening rooms. Your auditory sense is quite adept at interpreting
clues about your physical environment. Even with your eyes closed, it is
possible to get a good mental picture of the room or hall you are in by
listening to the ambience, or reflected sound energy, in the room. We are not
aware of our auditory sense in everyday life because it confirms what our
eyes identify as the environment. When we listen to recorded music,
however, there are no visual clues and we rely completely on our sense of
hearing. The introduction of two-speaker stereo systems over thirty years
ago brought dramatic improvement to high fidelity music reproduction.
With a carefully-designed system, and good recording, it became possible to
produce a good sonic picture of the original event. Unfortunately, our
listening rooms do not approximate the acoustics of a good concert hall, an
intimate jazz club, or a magnificent cathedral - our ears tell us where we
really are. Lexicon processors are designed to overcome this fundamental
limitation to two-speaker reproduction and bring us closer to the ultimate
goal of transporting ourselves to the original musical event.
Four basic algorithms are utilized: 5 channel or 7 channel Surround, Ambi-
ence, Reverberation, and Panorama. These algorithms create effects specifi-
cally designed to accurately reproduce any program material in your home.
The object is to increase the sideways-moving sound in a room, thus
increasing Spatial Impression, or SI. We accomplish this by either extracting
it from the original recording, with the Panorama or Surround effects, or by
generating a new acoustic environment with Ambience or Reverberation.
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