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GLOSSARY
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CINEMA DSP
Since the Dolby Surround and DTS systems were
originally designed for use in movie theaters, their effect
is best felt in a theater having many speakers and
designed for acoustic effects. Since home conditions,
such as room size, wall material, number of speakers, and
so on, can differ so widely, it’s inevitable that there are
differences in the sound heard as well. Based on a wealth
of actually measured data, YAMAHA CINEMA DSP uses
YAMAHA original sound field technology to combine
Dolby Pro Logic, Dolby Digital and DTS systems to
provide the visual and audio experience of movie theater
in the listening room of your own home.
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Dolby Digital
Dolby Digital is a digital surround sound system that
gives you completely independent multi-channel audio.
With 3 front channels (left, center, and right), and 2
surround stereo channels, Dolby Digital provides 5 full-
range audio channels. With an additional channel
especially for bass effects, called LFE (low frequency
effect), the system has a total of 5.1 channels (LFE is
counted as 0.1 channel).
By using 2-channel stereo for the surround speakers,
more accurate moving sound effects and surround sound
environment are possible than with Dolby Surround. The
wide dynamic range (from maximum to minimum
volume) reproduced by the 5 full-range channels and the
precise sound orientation generated using digital sound
processing provide listeners with previously unheard of
excitement and realism.
With this unit, any sound environment from monaural up
to a 5.1-channel configuration can be freely selected for
your enjoyment.
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Dolby Pro Logic II
Dolby Pro Logic II is an improved technique used to
decode vast numbers of existing Dolby Surround
software. This new technology enables a discrete 5-
channel playback with 2 front left and right channels, 1
center channel, and 2 surround left and right channels
(instead of only 1 surround channel for conventional Pro
Logic technology). A music mode is also available for 2-
channel sources in addition to the movie mode.
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Dolby Surround
Dolby Surround uses a 4 channel analog recording system
to reproduce realistic and dynamic sound effects: 2 front
left and right channels (stereo), a center channel for
dialog (monaural), and a surround channel for special
sound effects (monaural). The surround channel
reproduces sound within a narrow frequency range.
Dolby Surround is widely used with nearly all video tapes
and laser discs, and in many TV and cable broadcasts as
well. The Dolby Pro Logic decoder built into this unit
employs a digital signal processing system that
automatically stabilizes the volume on each channel to
enhance moving sound effects and directionality.
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DTS (Digital Theater Systems) Digital
Surround
DTS digital surround was developed to replace the analog
soundtracks of movies with a 6-channel digital sound
track, and is now rapidly gaining popularity in movie
theaters around the world. Digital Theater Systems Inc.
has developed a home theater system so that you can
enjoy the depth of sound and natural spatial
representation of DTS digital surround in your home.
This system produces practically distortion-free 6-channel
sound (technically, a left, right and center channels, 2
surround channels, plus an LFE 0.1 channel as a
subwoofer, for a total of 5.1 channels).
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LFE 0.1 channel
This channel is for the reproduction of low bass signals.
The frequency range for this channel is 20 Hz to 120 Hz.
This channel is counted as 0.1 because it only enforces a
low frequency range compared to the full-range
reproduced by the other 5 channels in a Dolby Digital or
DTS 5.1 channel systems.
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Matrix 6.1
The unit incorporates Matrix 6.1 decoder for Dolby
Digital and DTS multi-channel software that enables 6.1-
channel reproduction by adding the surround back
channel to existing 5.1-channel format. (The surround
back channel is created from surround left and right
channels, and outputted from virtual surround back
speaker.) With this additional channel, you can experience
more dynamic and realistic moving sound especially with
scenes with “fly-over ” and “fly-around ” effects.
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PCM (Linear PCM)
Linear PCM is a signal format under which an analog
audio signal is digitized, recorded and transmitted without
using any compression. This is used as a method of
recording CDs and DVD audio. The PCM system uses a
technique for sampling the size of the analog signal per
very small unit of time. Standing for “pulse code
modulation”, the analog signal is encoded as pulses and
then modulated for recording.
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Sampling frequency and number of
quantized bits
When digitizing an analog audio signal, the number of
times the signal is sampled per second is called the
sampling frequency, while the degree of fineness when
converting the sound level into a numeric value is called
the number of quantized bits.
The range of rates that can be played back is determined
based on the sampling rate, while the dynamic range
representing the sound level difference is determined by
the number of quantized bits. In principle, the higher the
sampling frequency, the wider the range of frequencies
that can be played back, and the higher the number of
quantized bits, the more finely the sound level can be
reproduced.
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