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En
Glossary
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HDMI
HDMI (High-Definition Multimedia Interface) is the first
industry-supported, uncompressed, all-digital audio/video
interface. Providing an interface between any source (such
as a set-top box or AV receiver) and an audio/video
monitor (such as a digital television), HDMI supports
standard, enhanced or high-definition video as well as
multi-channel digital audio using a single cable. HDMI
transmits all ATSC HDTV standards and supports 8-
channel digital audio, with bandwidth to spare to
accommodate future enhancements and requirements.
When used in combination with HDCP (High-bandwidth
Digital Content Protection), HDMI provides a secure
audio/video interface that meets the security requirements
of content providers and system operators. For further
information on HDMI, visit the HDMI website at
“http://www.hdmi.org/”.
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LFE 0.1 channel
This channel reproduces low-frequency 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.
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MP3
One of the audio compression methods used by MPEG. It
employs the irreversible compression method, which
achieves a high compression rate by thinning out the data
of hardly audible part to the human ears. It is said to be
capable of compressing the data quantity by about 1/11
(128 kbps) while maintaining a similar audio quality to
music CD.
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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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SILENT CINEMA
Yamaha has developed a natural, realistic sound effect
DSP algorithm for headphones. Parameters for
headphones have been set for each sound field so that
accurate representations of all the sound field programs
can be enjoyed on headphones.
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Virtual CINEMA DSP
Yamaha has developed a Virtual CINEMA DSP algorithm
that allows you to enjoy DSP sound field 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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WAV
Windows standard audio file format, which defines the
method of recording the digital data obtained by
converting audio signals. It does not specify the
compression (coding) method so a desired compression
method can be used with it. By default, it is compatible
with the PCM method (no compression) and some
compression methods including the ADPCM method.
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WMA
An audio compression method developed by Microsoft
Corporation. It employs the irreversible compression
method, which achieves a high compression rate by
thinning out the data of hardly audible part to the human
ears. It is said to be capable of compressing the data
quantity by about 1/22 (64 kbps) while maintaining a
similar audio quality to music CD.
01EN_DSP-AX463_B.book Page 74 Friday, February 1, 2008 2:09 PM
