Inter-m PAM-MPM4, Operation Manual

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PAM-MPM4 (CD MP3 TUNER Module)
Additional Explanation
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MP3 (MPEG AUDIO LAYER-3)
MP3 is one of music file formats that can contain music
with stereo sound quality similar to audio CD using a type
of MPEG which is compressive standards for audio and
video. About 3~5MB is sufficient if recording music for
3min~5min as the compression ratio is average 1Mb per
minute. In addition, 130 music or more can be contained
in a CD for songs or folk song if making music files with
MP3 differently from audio CD and MP3 has advantage in
play time of 10 hours. MP3 has also advantage of
compacting music into about 1/12 size while maintaining
sound quality of the CD level as it can remove frequency
range impossible for human to identify. For example,
capacity of 50MB or so can be achieved if extracting music
of a CD while maintaining sound quality of CD as it is but its
size can be largely reduced to 4~5MB if compressing and
converting it to a MP3.
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WMA (WINDOWS MEDIA AUDIO)
WMA is Microsoft’s multimedia compression method and is
technology to compress only music data from 'Window
Media Technologies'. It provides sound quality equivalent
to 128Kbps format of MP3 with 64Kbps format lower than
MP3. In other word, the file size of 1.2 MP3 provides same
sound quality as MP3.
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DIGITAL OUTPUT AND SPECIFICATIONS
Sound signal of a CD is recorded via digital-conversion and
digital sound signal is converted to analog signal by digital-
analog converter (DAC) within the usual player for output.
Conversely, electrical digital signals are substituted with
optical signal by coaxial cables, semiconductor or light
emitting diode (LED), etc and can be connected with other
devices with optical fiber cables. The device of the party
which received optical signals converts optical signals to
electrical signals for various treatments. Direct transmission
of digital data has advantage that there is less data error as