WHAT IS AN MD (MVl DISC)?
An MD is only 64 mm (25/s inches) in diameter, about half the
size of a conventional
CD. But an MD can be used to store
and playback a full 74 minutes of data such as a CD. Unlike
a CD, an MD comes in a plastic cartridge, so that it can be
handled with ease. The cartridge also protects the disc inside
from shocks, dust and scratches. Unlike cassette tapes,
which can become stretched or tangled, an MD is an
excellent durable media.
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There are two types of MDs: "Optical discs" and "Magneto-
optical discs". Both types use laser beams and optical pick-
up technology
to read recorded data during playback.
Optical discs
These are playback only discs. Like CDs, they are used as
prerecorded
music discs. You cannot record or edit them.
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Label
The shutter covers the
opening only on the non
labeled side of the MD.
Recordable
MO*i discs
These are recordable discs which can be recorded on again
and again, like cassette tapes. The recording method called
magneto-optical
technology
employs a laser and magnetism
to record signals, Therefore,
the quality of recorded sound
does not deteriorate
even after many playbacks and
recordings.
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Label
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The shutter covers the
.—————
opening on both sides of
the MD.
'1 MO: An abbreviation
of Magneto Optical
Ultra compact size made possible by ATRAC*2
technology
A newly developed
digital audio compression
technology
called the ATRAC system automatically
extracts only the
frequencies
that are actually audible to the human ear and
cuts the frequencies
which are inaudible. This compresses
the amount of data to be recorded to 1/5 of the normal
amount. The ATRAC system is based upon studies carried
out in the field of auditory psychology
and does not impair
the quality of the audible sound.
'2 ATRAC: An abbreviation
of Adaptive TRansform
Acoustic
Coding
Recording on the MD is performed differently from that of a
cassette tape or a DAT. Therefore,
the MD system is subject
to the following
restrictions.
"Toc* Full" is displayed
even if the recording time does
not reach the maximum
recordable
time of the disc (60-
minute or 74-minute)
"TOC Full" is displayed when 254 tracks are already recorded
on a disc, without respect to the recording time.
* Toe: An abbreviation
of Table Of Contents.
"TOC Full" is displayed
even if a disc is not fully
recorded on
If there are lots of emphasis data in a particular track, the
unit handles the data as index codes, and tracks are
counted, in addition, without respect to the time and number
of tracks.
The remaining time on a disc is not increased even after
some short tracks have been erased
When the remaining time on a disc is displayed,
it may not
be increased even after erasing short tracks because the
sections less than eight seconds are not counted.
Tracks cannot be joined (the COMBINE function does
not function)
Tracks created by editing may not be joined.
The total of the recorded time and the remaining time on
a disc does not match the maximum
recordable
time of
the disc (60-minute
or 74-minute)
Recording is performed
in a minimum unit of one cluster (two
seconds). Even if the recorded section is shorter than two
seconds, a two-second
space is needed in recording.
Therefore,
the available time becomes shorter.
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Track numbers may not be registered
properly
When recording from a CD with CD -
MD, small tracks may
be created depending
on the contents of a CD.
In addition, track numbers may not be registered properly
depending
on the contents of the CD.
Quick random access
One of the great features of the MD is that you can search
for desired tracks quickly. There are also quick and easy
functions for random playback, in which the order of the
tracks can be rearranged
at random, and for renumbering
tracks enabling them to be played in any order.
ENGLISH 17