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About MD (Mini Disc)
Playback-only MD
Recordable MD
Cartridge
Disc
Cartridge
Sound Cruise
Shutter
The MD (Mini Disc) is a new digital audio medium using a disc with a diameter of 64
millimeters. In spite of the small size, the MD has multiple functions, high audio quality
and recording/playback capabilities for up to 74 minutes.
Role of the cartridge
The MD cartridge has a pocket size of 68 mm × 72 mm with a thickness of 5
mm. The cartridge accommodates the 64 mm diameter disc for ease of
transportation and storage.
The internal disc is usually protected by the cartridge shells and shutter so no
dust, dirt, scratch or fingerprint is left on the disc and the disc handling is easy.
Two disc types
The MD (Mini Disc) includes two disc types, the recordable MD that can be recorded onto
and the playback-only MD that can exclusively be played back. Although both types of
discs are played in the same way, that is, by irradiating a laser beam on the disc and reading
signals from the reflected light, the ways they are recorded are completely different.
Playback-only MD
This type of disc is used in prerecorded MD software marketed in music stores. It cannot be
recorded by the user and data is recorded in the same way as a CD, i.e. according to the
presence or absence of small holes called pits. A disc recorded in this way is referred to as
an “optical disc”.
Recordable MD
This type of disc records data using the magnetism to allow repeated data recording
operations. A disc recorded in this way is referred to as an “MO (Magneto-Optical) disc”.
XM-228BK(B)-Eng. p.30-38 98.9.25, 4:24 PM32