Yamaha YMC S21 - neoHD AV System Owner's Manual page 53

Glossary
■ 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/".
■ 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 channels in
systems.
■ 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.
■ MPEG-4 AAC
An MPEG-4 audio standard. As it allows compression of data at a
bit rate lower than that of MPEG-2 AAC, it is used among others
for mobile telephones, portable audio players and other low-
capacity devices requiring high sound quality.
In addition to the above types of devices, MPEG-4 AAC is also
used to distribute contents on the Internet, and as such is
supported by computers, media servers and many other devices.
■ PCM (Linear PCM)
Linear PCM is a signal format under which an analog audio
signal is digitized, recorded and transmitted without using any
compression. 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.
■ 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.
■ 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.
■ "x.v.Color"
A color space standard supported by HDMI version 1.3. It is a
more extensive color space than sRGB, and allows the expression
of colors that could not be expressed before. While remaining
compatible with the color gamut of sRGB standards, "x.v.Color"
expands the color space and can thus produce more vivid, natural
images. It is particularly effective for still pictures and computer
graphics.