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(c) 1999-2001


The Compact Disc 'CD'..
The compact disc was launched in 1982. The first recording released on CD was Billy Joel's 52nd Street.  The CD offered the home consumer for the first time, high quality digital audio in a robust and convenient format. The main attractions for the CD was the ability to play your favorite 'record' more than just a few times without leaving scratches, noise or damage as the CD was very durable. The consumer also enjoyed instant access between tracks, the remote control facility and the small size.
The disadvantages at the launch was that few titles were available and the cost of the CD's was much higher than that of both vinyl and cassette tape.  CD player prices were also much higher than turntables and cassette decks back in 1982. But the catalogue of music through the 1980s quickly grew and player costs quickly reduced. By 1994 just 12 years after launch, the CD dominated the market in music sales in the UK and is still the dominant format.

Technical information:

The compact disc is read by a laser which receives a series of digital pulses from a track of bumps (125 nanometer high) as it follows a spiral track from the middle of the disc outwards. The track width is tiny at just 0.5 microns wide, with 1.6 microns separating the tracks. The data storage on a 74 minute CD is so vast (650MB) that the spiral track if it could be unwrapped would be almost 5 miles long. The CD initially rotates in the player at 500 rpm as the laser reads the inner tracks, the speed slowly decreases to 200 rpm as the outer tracks are read. This keeps the data rate constant as the laser traverses the disc. The digital sample rate is 44.1 kHz which is more than twice that of the highest audible frequency ensuring high resolution digital to analogue conversion. There is no contact between the laser reader and the disc during playback ensuring no physical wear of the disc. With careful handling and storage CDs will last more than a lifetime. 

James T Russell invented the optical audio system and holds a total of 22 patents. The CD was taken into production by the giant Philips and Sony corporations in 1982.

First CD released - Billy Joel 52nd Street
First CD released "Billy Joel" in 1982

20 Years of world wide music sales 1981- 2001
Total music sales from 1981 to 2001

The CD first released in 1982
The Compact Disk stores 74 Minutes
of music on a 650 MB Disc

NAD C520 CD Player
A modern CD Player from NAD
the retail price in the UK 170