DM-9090 (En)
9
MD system
The Mini Disc system has the features as summarized in the following.
1Like CD (Compact Disc), playback can be started from any position. (Random access)
2It uses a disc with a diameter of 64 mm that is accommodated in a cartridge.
3Two types of discs can be used. (playback only discs, recordable / playable discs).
4Up to 74 minutes of recording or playback is possible using high-efficiency coding technology.
5Countermeasure against vibration is taken using semiconductor memory chip.
Playback-only Mini Disc
This type of MD can be used only for playback,
and is used by the commercially-available mu-
sic MD software packages. The playback-only
MD is an optical disc like the Compact Disc
(CD). The signals are recorded as the presence
or absence of small pits and read out by an
optical, non-contact pickup.
Recordable Mini Disc
This MD is a magneto-optical disc which can
be recorded by magnetic field modulation. To
record signals, laser light is irradiated from the
bottom side of the magneto-optical disc and
magnetic field is applied from the upper side
of it.
Sound-skip prevention memory
During playback, this unit always stores signals in memory temporarily to prevent sound from being skipped in case of vibration. As a result, even
when the data from the optical pickup is interrupted due to vibration, etc., the music will not be interrupted because the memory holds the data for
several seconds.
During normal
playback In case of vibration
High-efficiency coding technology “ATRAC” (Adaptive TRansform Acoustic Coding)
The Mini Disc has only a half the size of the Compact Disc but provides the same recording time. This is made possible by ATRAC*, a newly developed
high-efficiency coding technology.
The ATRAC compresses the music data to about 1/5 the amount of data which would be obtained with conventional technology, by cutting off the
sound components which do not pose problem in audition even when they are not present. This has made it possible to record or play up to 74 minutes.
Small sound near large
sound
Sound does not af-
fect the sensitivity
of ears
A small sound is not audible
to human ears if it is
produced at the same time
as a large sound. (Masking
effect)
Sensitivity of ears
Lowest frequencies Highest frequencies
Monaural recording
This unit can record a longer period of sound in monaural (monaural long-play mode). In this mode, the recording time of the disc is about double that
in the stereo mode.
The Mini Disc recorded in the monaural mode cannot be played with equipment which is not compatible with monaural playback. ^
D.R.I.V.E. (Dynamic Resolution Intensive Vector Enhancement) system
This unit incorporates the KENWOOD-original “20-bit REC D.R.I.V.E.” system so that, not to mention the CD, analog sources such as the tuner and
analog disk turntable can also be recorded with high-quality 20-bit recording.
The digital inputs include both optical and coaxial input jacks so that high-quality recording is possible from any digital equipment.
1The reproducibility of small signals is improved drastically for an excellent reproduction of fine reverberations of music. The excellence is also
remarkable in the feeling of stability, presence, attack sound and bass reproduction.
2The D.R.I.V.E. system maintains the correlation between the musical components of the input and output signals and does not cause any sound
degradation from the principle.
Reproduced sound
Mini Disc When the readout from disc
is interrupted momentarily
due to vibration or shock, the
reproduced sound from the
memory will not be
interrupted.
The sound data for several
seconds is always stored
during playback.
Digital memory
Several sec. of data
Reproduced sound
Lowest and highest
frequencies are not audible
unless the sound has a
certain level of volume.
MONITOR function
This unit can be used as a 24-bit D/A converter by setting the MONITOR key. Refer to “MONITOR key”. £
12
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39