Launching players and discs together
Sony released the CDP-101 in Japan on 1 October 1982 at a price of 168,000 yen. CBS Sony supplied fifty CD titles across classical, pop, rock and other music, including Billy Joel’s 52nd Street. A stable commercial market required players and available discs that could work across different machines.
Sony prepared disc-production facilities and clean rooms near Ōigawa in Shizuoka Prefecture. Its history records the final decision to use polycarbonate only in August 1982, with mass production starting in mid-September and adjustments continuing shortly before release. The node marks October sales in Japan, distinct from laboratory demonstrations and releases elsewhere.
References: [4]
The 1979 prototype had earlier specifications
On 8 March 1979, Philips demonstrated a prototype called Pinkeltje to the press in Eindhoven, using an 11.5-centimeter disc. Earlier development had shown that optical reading avoided stylus contact without automatically preventing signal interruptions from dust, scratches and manufacturing defects. Analog optical-audio approaches performed poorly, making digital encoding and error handling central engineering tasks.
Philips subsequently sought a partner in Japan, and Sony joined. Alternating meetings in Eindhoven and Tokyo negotiated diameter, playing time, sampling rate, quantization and recording format. A shared standard emerged in June 1980, using a 12-centimeter disc, 44.1-kilohertz sampling and 16-bit quantization per channel. Error-correction and modulation schemes went through discussion, simulation and disc tests. The eventual system was a joint development beyond either company’s earlier prototype.
References: [1]
From a glass master to optical reading
During manufacture, encoded data controls a laser exposing a photosensitive layer on a rotating glass master. Development forms microscopic pits, and metallization and electroforming produce molds for pressing the track into transparent plastic substrates. Finished discs have reflective and protective layers. Home players read these mass-replicated prerecorded media rather than writing music onto them.
During playback, laser light passes through the substrate and focuses on the information layer. Changes between pits and flat areas alter the reflected signal reaching a photodetector. Servos maintain focus and follow the spiral track, while rotational speed changes with reading position. The player recovers channel bits and reverses modulation and encoding to reconstruct audio data.
References: [2]
Correcting errors and concealing unrecoverable gaps
The two audio channels are sampled periodically, with each sample represented by 16 bits. Check and control information is added, and eight-to-fourteen modulation converts data into sequences suitable for optical recording. Playback reverses modulation, buffers data and handles errors before digital-to-analog conversion and filtering produce left and right signals for an amplifier.
The cross-interleaved Reed–Solomon code, CIRC, uses additional check symbols to detect and correct errors. Interleaving spreads adjacent physical damage over different data groups during decoding, reducing concentrated loss from a scratch. When damage exceeds correction capacity, a player may interpolate neighboring samples or fade to silence. Correction restores original data; concealment reduces audible disturbance without necessarily restoring it.
A shared disc format in different markets
The standard fixes the relationship between recordings and playback systems while allowing different mechanisms, controls and circuits. Philips Technical Review described the CD100 and its system in 1982, but technical publication and consumer availability in each country had separate dates. Philips’ archives date European market promotion to 1 March 1983.
Track selection, time display and programmed playback changed how listeners found music. Initial prices were high, however, and record companies had substantial investment in conventional records. The new format did not immediately replace earlier media. The Japanese launch connected common specifications, disc replication and home players; later supply and catalogue expansion brought the system to wider audiences.