Glossary
Digital Cinema Sound
This is the generic name of the surround sound
produced by digital signal processing
technology developed by Sony. Unlike
previous surround sound fields mainly directed
at the reproduction of music, Digital Cinema
Sound is designed specifically for the
enjoyment of movies.
Dolby Digital
This sound format for movie theaters is more
advanced than Dolby Pro Logic Surround. In
this format, the rear speakers output stereo
sound with an expanded frequency range and a
sub woofer channel for deep bass is
independently provided. This format is also
called "5.1" because the sub woofer channel is
counted as 0.1 channel (since it functions only
when a deep bass effect is needed). All six
channels in this format are recorded separately
to realize superior channel separation.
Furthermore, since all the signals are processed
digitally, less signal degradation occurs.
Dolby Pro Logic II
Dolby Pro Logic II creates five full-bandwidth
output channels from two-channel sources.
This is done using an advanced, high-purity
matrix surround decoder that extracts the
spatial properties of the original recording
without adding any new sounds or tonal
colorations.
Dolby Pro Logic Surround
As one method of decoding Dolby Surround,
Dolby Pro Logic Surround produces four
channels from two-channel sound. Compared
with the former Dolby Surround system, Dolby
Pro Logic Surround reproduces left-to-right
panning more naturally and localizes sounds
more precisely. To take full advantage of
Dolby Pro Logic Surround, you should have
one pair of rear speakers and a center speaker.
The rear speakers output monaural sound.
Surround sound
Sound that consists of three elements: direct
sound, early reflected sound (early reflections)
and reverberative sound (reverberation). The
acoustics of the surrounding space affect the
way these three sound elements are heard.
Surround sound combines these sound
elements in such a way that you actually can
sense the size of the venue, as well as its type.
• Types of sound
Early reflections
Direct sound
• Transition of sound from rear speakers
Direct sound
Level
Early
reflections
Reverberation
Early reflection time
Reverberation
Time
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