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CDRWAPPENDIXIX

(CONT )

ENGLISH

A session is defined as an area including lead-in, program data and lead-out.

A CD-R recorder that supports multisession recording can write a disc that will have multiple sessions linked together, each containing their own lead-in, program and lead out.

Any multisession-supported CD reader can access the data, whether it was written in the first session or a subsequent session.

Contrast this to the recording structure of a pressed CD-ROM or a CD-R written in “Disc at Once” mode that contains just one lead- in area and one lead-out area.

WHAT IS THE RECORDING SPEED OF CD-R?

The “speed” rating of a CD-Recordable/Rewritable determines how fast it can record data to blank CD-R media.

Speed designators, such as “1X”, “2X”, “4X” and “6X” define multiples of the original playback speed of first generation CD-ROM players:

For a CD-ROM player or CD-Recordable/Rewritable, a 1X speed translates to 153,600 Bytes per second. This is usually rounded down to 150 Kb per second. Therefore, a “1X” recorder writes 150 Kb per second to the CD-R media.

Likewise, a “4X” recorder records at 600 Kb per second.

NOTE: THERE ARE SOME VARIATIONS IN MEASURING SPEED, BECAUSE THERE ARE RECORDING MODES THAT PROVIDE MORE THAN 2,048 DATA BYTES PER BLOCK (AUDIO IS RECORDED AT 2,352 BYTES PER BLOCK).

NOTE: SOME CD-RECORDABLE/REWRITABLES HAVE A

DIFFERENT READING SPEED THAN THEIR RATED RECORDING

SPEED. FOR INSTANCE, THIS “8X4X32” CD-RECORDABLE /

REWRITABLE CAN WRITE AT 8X SPEED ON CD-R, 4X SPEED

ON CD-RWAND READ BACK AT 32X SPEED.

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