CD-Digital Audio (CD-DA)
The first standard CD format was the one used to produce audio CDs that could play in
all regular CD players:CD-DigitalAudio,orCD-DA. The CD-DA standard was defined in
what is called the Red Book, a specification developed by the two originators of the CD
technology, the Royal Philips Electronics Company and the Sony Corporation. The Red
Book standard, issued in 1980, defines the technical specification for CD-DA (audio CD),
including sampling and transfer rates, the data format for the digital audio, and the phys-
ical specifications for compact discs, including the media’s size and the spacing of tracks.
The Red Book defined the standard for the structure of the media and how a CD is read
that is still used today.
The technical details of the Red Book standard include:
16-bit sample.
Sampling is at 44.1kHz (kilohertz), which is about
twice the highest frequency that humans can hear.
Sampling is done in stereo.
Each one second of sound stored on the CD requires 176,400 bytes.Compact Disc-Read-Only Memory (CD-ROM)
ThelargecapacityoftheCDwasattractivetononmusicproducersaswell,includingsoft-
ware publishers, database producers, and multimedia developers. The CD-ROM holds
about 640 million bytes of data. The CD-ROM technology had approximately the same
speed as the CD-DA, which was designated as 1X (one times) the relative speed of a music
CD at about 150KB per second.
Chapter 10: CD-ROMs and DVDs^203
Figure 10-1. A compact disc can be used for data or music