Looking At The Controls - Sony MZ-R30 Operating Instructions Manual

MZ-R30 Operating Instructions
Microphone: stereo mini-jack, 0.22 - 0.78 mV
Line in: stereo mini-jack, 69 - 194 mV
Optical(Digital) in: optical (digital) mini-jack
Outputs:
Headphones: stereo mini-jack, maximum
output level 5mW + 5mW, load impedance
16 Ohm
Line out: stereo mini-jack, 194mV, load
impedance 10 kOhm
What is MD?
How MiniDisc works
MiniDisc (MD) comes in two types:
premastered (prerecorded) and
recordable (blank). Premastered
MDs, recorded at music studios,
can be played back almost
endlessly. However, they can´t be
recorded on or over like cassette
tapes. To record, you must use a
"recordable MD".
Premastered MDs
Premastered MDs are recorded and
played like regular CDs. A laser
beam focuses on the pits in the
surface of the MD and reflects the
information back to the lens in the
recorder. The recorder then
decodes the signals and plays them
back as music.

Looking at the controls

The recorder
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Carrying case (1)
Dry battery case (1)
Recordable MDs
Recordable MDs, which use
magneto-optical (MO) technology,
can be recorded again an again. The
laser inside the recorder applies
heat to the MD, demagnetizing the
magnetic layer of the MD. The
recorder then applies a magnetic
field to the layer. This magnetic field
corresponds exactly to the audio
signals generated by the connected
source. (The north and south
polarities equate to digital "1" and
"0".) The demagnetized MD adopts
the polarity of the magnetic field,
resulting in a recorded MD.
Quick Random Access
Like CDs, MDs offer instantaneous
random access to the beginning of
any music track. Premastered MDs
are recorded with location addresses
corresponding to each music
selection. Recordable MDs are
manufactured with a "User TOC
Area" to contain the order of the
music. The TOC system is similar to
the "directory management system"
of floppy disks. In other words,
starting and ending addresses for all
music tracks recorded on the disc
are stored in this area. This lets you
randomly access the beginning of
any track as soon as you enter the
track number (AMS), as well as
label the location with a track name
as you would a file on a diskette.
How the MiniDisc got so small
The 2.5 inch MiniDisc, encased in a
plastic cartridge that looks like a 3.5
inch diskette, uses a new digital audio
compression technology called ATRAC
(Adaptive TRansformation Acoustic
Coding). To store more sound in less
space, ATRAC extracts and encodes
only those frequency components
actually audible to the human ear.
Shock-Resistant Memory
One major drawback of optical read
systems is that they can skip or mute
when subjected to vibration. The MD
system resolves this problem by using
a buffer memory that stores audio
data.