Digital Audio - Philips CDR880 Service Manual

Making your own CDs - the final functionality
for your audio system
This unique Philips CD-Recorder gives you the capability, for the first
time, to make your own top-quality audio CDs, on either 'write-once'
CD-Recordable discs or re-usable CD-ReWritable discs. Subject to the
digital copy constraints of the SCMS system, you can make CDs
from all analogue or digital sources in your audio system.
Discs can be recorded all at once, or in stages, known as 'sessions'.
Just as on a prerecorded CD, you can put track numbers on your own
discs, automatically or manually, depending on the source and your own
preference. And when 'finalized' for playback, these discs behave in
exactly the same way as your regular prerecorded CDs.
CD-Recordable - The 'Write-
Once' Discs
Blank CD-Recordable (CD-R) discs
COMPACT feature an organic dye layer for
recording, applied over a
substrate containing a
DIGITAL AUDIO
wobbulated 'pre-groove' to
Recordable
groove' is FM modulated with time code
guide the laser beam. The 'pre-
and other disc information. The average
wobbulation frequency is used to control
the turntable speed, while the time code
is used to position the recordings on the
disc. During recording, the laser forms
'bumps' in the dye layer, which have the
same effect as the pits in a pre-recorded
CD. When fully recorded and 'finalized',
CD-R discs are fixed for life, and will play
on all CD players and recorders.
CD-Rewritable - The Erasable
And Reusable Disc
Blank CD-ReWritable (CD-RW) discs
use 'phase change' technology for
COMPACT recording, and the same
wobbulated 'pre-groove'
principle. A low-reflectance
DIGITAL AUDIC = domain of amorphous (or non-
crystalline) phase, is produced
when the laser heats the recording layer
rapidly above its melting point of
500-700° C. Cooling quickly, this
amorphous domain 'freezes' and becomes
reflective. If, on the other hand,
the recording layer is heated to a rather
lower temperature for a somewhat longer
time, a light-diffusing crystalline phase is
formed. Because these changes are
reversible, CD-RW discs can be erased
and rewritten, at least a thousand times.
During recording, individual tracks
can be erased; when fully recorded and
'finalized', these discs must be erased
completely before re-use. Finalized
CD-RW discs will play on all CD-RW-
compatible CD players and recorders.
Philips will start to make it's CD-players
compatible with RW-discs in 1998.
Note: The CDR-870 is designed to use
CD-R and CD-RW discs optimized for
audio recording, and bearing these
logos.CD-R and CD-RW discs produced
specially for use with CD-R/RW computer
drives are not suitable. The logo's on
these discs do not contain 'Digital Audio'.
Analogue Recording
This is just like recording on to
cassette tape. You adjust the record level
control so that the loudest passages fill
the blue section of the record level meter
on the display, without going into the red
overload section.
If you choose automatic track
numbering, the CDR 870 inserts a new
track number each time it detects a
3-second pause in the music. With manual
track numbering, you can insert track
numbers any place you like during
recording. When the recording stops,
the discs's temporary Table Of Contents
is automatically updated, and when you
come back to resume recording,
the player automatically finds the end of
the last recording session.
Digital Recording
No record level setting is required for
digital recording; the level is regulated in
the digital input signal.
If you choose automatic track number-
ing, the CDR 870 inserts track numbers
directly from the source material.
With manual track numbering, you can