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En
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Audio information
Dolby Digital
Dolby Digital is a digital surround sound system that gives you
completely independent multi-channel audio. With 3 front channels
(front L/R and center), 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 unprecedented 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.
Dolby Pro Logic II
Dolby Pro Logic II is an improved technique used to decode vast
numbers of existing Dolby Surround sources. 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. There are three modes available: “Music mode” for music
sources, “Movie mode” for movie sources and “Game mode” for
game sources.
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.
DTS Digital Surround
DTS digital surround was developed to replace the analog soundtracks
of movies with a 5.1-channel digital sound track, and is now rapidly
gaining popularity in movie theaters around the world. DTS, 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 5.1-
channel sound (technically, left, right and center channels, 2 surround
channels, plus an LFE 0.1 channel as a subwoofer, for a total of 5.1-
channels).
LFE 0.1 channel
This channel reproduces low-frequency bass signals. The frequency
range of this channel is from 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 Dolby Digital or DTS
5.1-channel systems.
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.
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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Sound field program information
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 designed for acoustic effects. Since home conditions,
such as room size, wall material, number of speakers, and so on, can
differ so widely, it is inevitable that there are differences in the sound
heard. Based on a wealth of actually measured data, Yamaha
CINEMA DSP uses Yamaha original DSP technology to combine
Dolby Pro Logic, Dolby Digital and DTS systems to provide the
audiovisual experience of movie theater in the listening room of your
own home.
SILENT CINEMA
Yamaha has developed a natural, realistic sound effect DSP algorithm
for headphones. Parameters for headphones have been set for each
sound field program so that accurate representations of all the sound
field programs can be enjoyed on headphones.
Virtual CINEMA DSP
Yamaha has developed a Virtual CINEMA DSP algorithm that allows
you to enjoy DSP surround effects even without any surround
speakers by using virtual surround speakers. It is even possible to
enjoy Virtual CINEMA DSP using a minimal two-speaker system that
does not include a center speaker.
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Video information
Component video signal
With the component video signal system, the video signal is separated
into the Y signal for the luminance and the P
B
and P
R
signals for the
chrominance. Color can be reproduced more faithfully with this
system because each of these signals is independent. The component
signal is also called the “color difference signal” because the
luminance signal is subtracted from the color signal. A monitor with
component input jacks is required in order to output component
signals.
Composite video signal
With the composite video signal system, the video signal is composed
of three basic elements of a video picture: color, brightness and
synchronization data. A composite video jack on a video component
transmits these three elements combined.
Glossary
