The idea of a small phonograph record read by a light beam that could play for more than an hour, with studio sound quality and never wear out, originated during the intensive development of home video discs by many companies during the mid-1970s. Eventually almost all manufacturers accepted that the best video system was the laser optical videodisc – and this spun off the laser optical audio Compact Disc.

The first demonstration of a prototype CD was given by Philips at their headquarters in Eindhoven, Holland in the spring of 1979. But Philips could not go it alone. Support from the Japanese giants Sony and Panasonic was essential.

The world had changed drastically since the introduction of the Compact Cassette – in the mid-1960s – when Philips ruled the roost in Europe by giving free licences for rivals to make the CC system, on condition that they make no changes whatsoever to the basic design. Japan was becoming all-powerful in audio and video.

The basic principle of CD is simple to describe but devilish hard to put into practice. A disc pressed from plastics has a spiral of microscopically small pits and bumps in the surface, instead of a groove. The surface pattern is read by a finely focussed laser beam which reflects back into a light sensitive cell, similar to that used in a camera for automatic exposure control. The light beam flickers and the light cell produces an on/off electric signal (digital ‘words’) which is decoded to make music.

Each pit or bump is only around one micron in size, which is one millionth of a metre, in size. By comparison the groove of a vinyl LP is around 50 microns wide, which is the same width as an average human hair. Specks of dusts are huge by comparison. So the discs have to be made in surgically clean air conditions. Philips liked to remind us that if a CD were enlarged to the size of the Roman Colosseum, the pits would be the size of match tips.

Philips was lucky that Akio Morita, the Western-thinking founder and then-boss of Sony, liked the idea of Compact Disc. Sony and Philips signed a deal in 1980 and Japanese and Dutch engineers worked together to improve the system.

Most importantly they increased the hi-fi resolution from 14 bit words to 16 bits. They also agreed on a standard which would be the same all round the world, with none of confusion caused by the different analogue TV systems then used (PAL for Europe, NTSC for the US and Japan and SECAM for Russia and France).

Sony and Philips agreed on a single-sided disc, five inches in diameter, read from the centre out (the opposite to LPs), and holding over 70 minutes of continuous hi fi stereo. Philips’ original plan had been for just 1 hour a side, but Akio Morita told his engineers to stretch it to 74 minutes; he wanted to hear his conductor buddy Herbert von Karajan’s recording of Beethoven’s Ninth Symphony without having to get up from his sofa.

Unless a CD is badly made or misused, it need never wear out. There is no physical contact between the laser mechanism and the disc; the laser light beam literally looks at the disc.

The CD standard also cleverly interleaves the left and right stereo channels and adds extra bits for ‘error correction’. This allows the player to reconstruct a perfect signal even when there are gaps in the digital stream, caused for instance by blemishes on the disc surface. If you drill a small hole through a CD it will still play perfectly. If you have an old CD, go ahead and try it.

The big breakthrough for CD came when Sony’s bitter rival, Matsushita (which makes Panasonic and Technics brand gadgetry) backed CD as the new world standard. After that, all the other companies had to fall in line.

CD went on sale in Japan, in October 1982, the next year in Europe and after that in the US.

At launch Philips made a marketing mistake that has never been forgotten. A full page double spread in the Sunday Times March 6, 1983 pledged that CD was “giving you pure, perfect sound that will last for ever. [We mean eternity]”.

Pundits queued up to remind us that nothing is literally perfect or ever-lasting.

Although the slogan was quickly canned, the memory lingered on. Some hi fi buffs argued from the start (some still argue) that digital sound from a CD cannot be as good as analogue sound from vinyl. There is currently a boom in LP sales, but that is partly because CD is being killed off by the record industry which can save money by selling music on line – without the hassle of pressing discs, printing album art and sleeve notes, and then warehousing it all before shipping long distance in lorries.

Resistance to CD is as old as CD. In February 1983 British magazine Hi Fi News published the thoughts of Ivor Tiefenbrun, founder of Linn (then famous for its turntables, later famous for CD players and now famous for digital streaming): “CDs very, very substantially distort, degrade and compress the range of pitch relationships characteristic of virtually all music…..if people listen to music reproduced on a compact disc player or on a digitally mastered disc…no real emotion whatsoever is experienced, other than irritation”.

Defence of CD is equally old. Soon after launch Oscar and Grammy-winning audio engineer and musician John Eargle came up with the never-bettered quote: “If you have heard just one CD that sounds good to your ears, then that proves the system technology works; everything else you hear and don’t like is a fault in the recording, the pressing or the reproduction – not the basic technology”.

For those with an interest in history, here is the timeline of how it all came to pass:

May 17 1978 Philips announces Compact Disc, with 14-bit linear coding
November 1978 Philips describes the technical basics of CD in a lecture to the AES (Audio Engineering Society)
March 8 1979 Philips unveils a prototype CD player at a press conference in Eindhoven
June 1980 Philips signs with Sony
January 1981 Matsushita signs up too
October 1980 Philips announces a new standard, agreed with Sony. Still 44.1 kHz but 16-bit
October 1980 Philips and Sony announce a prototype for the all-important Japan Audio Fair
September 1981 Philips says CD “now virtually worldwide standard” and promises commercial launch expected before the end of 1982
October 1982 CD went on sale in Japan – demand outstripped supply

It was the same in the UK for the first euphoric six weeks after its commercial launch in March 1983.

Jan Timmer of Polygram (later head of Philips) predicted in May 1983 that there would be LP/CD parity by 1989 and CD would “bury the black disc by 1993”.

But the LP is still alive and well…

Monoline Technology

This is how EMI Compact Disc (Holland) described the single, enclosed production line process:

Each monoline machine accomplishes the complete process – from injection moulding of the clear playing surface of the CD, through vacuum coating of this disc with a reflective aluminium layer and the application of a protective laquer, to printing the label on the non-playing surface.

The production of each CD takes 8.5 secs, within a totally ‘clean’ atmosphere (many times cleaner than that required in an operating theatre), so that no dust particles can adhere to the discs during manufacture.

The production of CDs before the development of monoline manufacture was a much longer process, which had to be carried out in a clean room atmosphere.

All air entering the entire manufacturing space was very finely filtered, and staff had to wear dust free ‘space suits’, masks and gloves.

This was essential to prevent the smallest speck of dust reaching the unvarnished discs as they were transferred from one machine to another for different stages in the production process.