Compact Disc - The Inside Story

Postscripts & References

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Postscript One - 1996

I thought it was worth-while spending an evening converting these articles into HTML format, and half a day scanning and processing the figures, even though the articles were written five to eight years ago. All of the technical details still apply, although some of the forecasts for the future were somewhat wrong (as is usually the case for nearly all attempts to prophesise the future).

The imminent release of the new DVD (Digital Video Disc) optical disc format promises a whole new era of high quality audio and video. At the least, it will probably result in the eventual demise of video tapes as a means of hiring movies (there I go again).

DVD has a base data capacity of 4,700 megabytes, and in a double-sided format it contains up to 17,000 megabytes. It is the same size as a standard CD, but has more than 26 times the data capacity. I have strong hopes that audio recording industry will use this new technology to improve the sample rate (eg. upgrade 44,100 samples/sec to 88,200) and the number of bits of resolution (eg. upgrade 16 to 22) in audio recordings to make no question of the quality of digital audio (in terms of frequency response, distortion, dynamic range and noise floor) being superior to all analog formats.

If you would like to know more technical details, read the article "CDs for the Gigabyte Era" by Tom R. Halfhill in Byte Magazine, October 1996, pp 139-144.

A good list of links for digital recording and DVD is at http://www.hut.fi/Misc/Electronics/audio.html#digirecord.

The technical details of DVD are at http://www.mpeg.org/MPEG/dvd.html.

Keep those discs turning and listen to music...
Glenn Baddeley
15 October 1996.

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Postscript Two - 1999

This year there have been some major revelations in the field of high resolution digital audio for consumers. In February the steering committee of the DVD Forum approved the specifications for DVD Audio. Even though the data capacity of a DVD disc is seven times that of a conventional CD disc, to achieve a nominal 74 minutes of play back time at the highest resolution in the specification, a lossless compression scheme is used, called Meridian Lossless Packing (MLP).

There are quite a few sampling frequencies supported, 48kHz, 96kHz, 192kHz and 44.1kHz, 88.2kHz, 176.4kHz. The bit resolution can be 16, 20 or 24 bits. Two channel stereo can be recorded at the highest sampling freqency and bit resolution, while up to six channels of audio can be recorded at lower rates.

Analog Devices Inc. have been quick off the mark and they are the first semiconductor manufacturer to release a stereo audio DAC chip (AD1853) which supports the complete DVD Forum specification for enhanced digital audio, which also includes backward compatibility with standard CD audio and digital de-emphasis.

So, the stage is set for some exciting advances, and hopefully, some fantastic recordings which we all can enjoy.

Power to the music listeners,
Glenn Baddeley
27 June 1999.


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References

Here is a list of magazine articles (newest to oldest) which I used to help write this series. They go into more detail in a lot of areas.

Richard Lambley, Optical Disc Storage, Electronics & Wireless World magazine, January 1989, pp24-27

Ken Pohlmann, Digital Domain - A Bit (Or Two) Better, Audio magazine, October 1987, p41-43

Ken Pohlmann, Digital Domain - Minding your P's and Q's, Audio magazine, March 1987, p26-30

Neville Williams, Compact Disc Players - 2, Electronics Australia magazine, March 1987, pp92-98

Neville Williams, Compact Disc Players - 1, Electronics Australia magazine, January 1987, pp88-93

J.R. Watkinson, Subcodes Explained, Electronics & Wireless World magazine, September 1986, pp26-30

Ken Pohlmann, Digital Domain - Aural Arguments, Audio magazine, July 1986, p19

Ken Pohlmann, Digital Domain - Choice Chips, Audio magazine, May 1986, pp36-38

J.R. Watkinson, Digital Audio Editing - 2, Electronics & Wireless World magazine, April 1986, pp52-54

J.R. Watkinson, Digital Audio Editing - 1, Electronics & Wireless World magazine, March 1986, pp29-32

J.R. Watkinson, Compact Disc Mastering, Electronics & Wireless World magazine, February 1986, pp47-50 & 62

J.R. Watkinson, Compact Disc Players - 2, Electronics & Wireless World magazine, November 1985, pp29-33

J.R. Watkinson, Compact Disc Players - 1, Electronics & Wireless World magazine, August 1985, pp52-55

J.R. Watkinson, Channel Code and Disc Format - 2, Electronics & Wireless World magazine, June 1985, pp80-82

J.R. Watkinson, Channel Code and Disc Format - 1, Electronics & Wireless World magazine, May 1985, pp27-28

J.R. Watkinson, Principles of optical storage - 2 - Focus and tracking mechanisms, Electronics & Wireless World magazine, April 1985, pp43-46

J.R. Watkinson, Principles of optical storage - 1, Electronics & Wireless World magazine, March 1985, pp70

Ken Pohlmann, Digital Domain - Keeping Your Distance, Audio magazine, February 1985, pp10-12

Ken Pohlmann, Digital Domain - Optimum Optics, Audio magazine, January 1985, pp26-30

J.R. Watkinson, The Compact Disc System, Electronics & Wireless World magazine, January 1985, pp69-71

Martin Colloms, Compact Disc Players, Hi-Fi News & Record Review magazine, March 1983, pp49-52

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Copyright © 1998, 1999, 2005 Glenn Baddeley.
http://werple.net.au/~gnb/mac-cdis/cdps.html was last updated 27 February 2005.