简要视音频发展编年史

转自一外国牛人博客

 

First, I'd like to apologize for not posting any articles lately. I've been busy completing financial reports, taxes, Spring break with the kids, and a bad cold... Anyhow, now that I have more time, I hope to get the blog back on track with more information about our development progress. Before I write more about Amplio Audio's development, I'd like to write a about the A/V industry, with a slant toward the audio side and the technology for listening to music.

Warning - this turned out to be a very long post (sort of makes up for the lack of posts during the previous month). Once I started gathering information, it just exploded. I would discover information about one thing and that would include a link to another, so I just kept gathering info. And like a poor editor, I just couldn't cut anything out... This is the timeline I came up with:

1860	The earliest known recording was created by Édouard-Léon Scott de Martinville, the inventor of the phonautograph. The recordings were not intended for listening; the idea of audio playback had not been conceived. Rather, Scott sought to create a paper record of human speech that could later be deciphered. But the phonautograph recording, or phonautogram, was made playable by scientists at the Lawrence Berkeley National Laboratory. The 10-second recording of a singer crooning the folk song “Au Clair de la Lune” was discovered in March 2008 in an archive in Paris by a group of American audio historians.
1874	Ernst W. Siemens was the first to describe the "dynamic" or moving-coil transducer, with a circular coil of wire in a magnetic field and supported so that it could move axially. He filed his U. S. patent application for a "magneto-electric apparatus" for "obtaining the mechanical movement of an electrical coil from electrical currents transmitted through it".
1876	Alexander G. Bell patented the telephone - the first electrical device for audible transmission.
1877	Thomas Edison invents the phonograph, which uses an engraved wax cylinder that rotates against a stylus.
1878	Ernest W. Siemens granted patent for a nonmagnetic parchment diaphragm as the sound radiator of a moving-coil transducer. The diaphragm could take the form of a cone, with an exponentially flaring "morning glory" trumpet form. This is the first patent for the loudspeaker horn that would be used on most phonographs players in the acoustic era. The first music is put on record: cornetist Jules Levy plays "Yankee Doodle."
1881	Clement Ader, using carbon microphones and armature headphones, accidentally produces a stereo effect when listeners outside the hall monitor adjacent telephone lines linked to stage mikes at the Paris Opera.
1887	Emile Berliner invents the gramophone, which uses a disc rather than a cylinder as the recording medium. The discs are flat, measure 7 inches in diameter, and can hold up to 2 minutes of recorded sound. The master disc is composed of zinc covered with a thin layer of acid-resistant wax.
1888	Thomas Edison introduces an electric motor-driven phonograph.
1894	Guglielmo Marconi made radio history when at the age of 20 he invented his spark transmitter with antenna at his home in Bologna, Italy.
1898	Valdemar Poulsen patents his "Telegraphone," recording magnetically on steel wire.
1900s	Boom in recorded music leads to copyright questions.
1900	Valdemar Poulsen unveils his invention to the public at the Paris Exposition. Austria's Emperor Franz Josef records his congratulations.
1901	The new "78 rpm" disc technology is developed. The Victor Talking Machine Company is founded by Emile Berliner and Eldridge Johnson. Experimental optical recordings are made on motion picture film. Guglielmo Marconi, using a 122-metre (400-foot) kite-supported antenna for reception, successfully transmitted a radio message from his company's new high-power station at Poldhu, Cornwall to Signal Hill in St John's, Newfoundland. The distance between the two points was about 3,500 kilometres (2,100 miles).
1906	Lee DeForest invents the triode vacuum tube, the first electronic signal amplifier. Victor Talking Machines Company introduces the Victrola.
1907	Boris Rosing filed his first patent on a television system, featuring a very early cathode ray tube as a receiver, and a mechanical device as a transmitter.
1909	WHA, originally 9XM, Madison Wisconsin was constructed by Edward Bennet and Earle Terry. KCBS traces its lineage back to "San Jose Calling", FN, 6XE, 6FX, SJN, and then KQW, built by Charles David Herrold in San Jose, California. These are the first stations to broadcast radio.
1910	Enrico Caruso is heard in the first live broadcast from the Metropolitan Opera, NYC.
1912	Major Edwin F. Armstrong is issued a patent for a regenerative circuit, making radio reception practical.
1913	The first "talking movie" is demonstrated by Thomas Edison using his Kinetophone process, a cylinder player mechanically synchronized to a film projector.
1915	Harold Arnold began program at Bell Telephone Laboratories to improve phonographic sound recording. The first priority was the electronic amplifier using the new vacuum tube, second was the microphone, and third was the loudspeaker that would improve the "balanced armature" units developed for public address.
1916	A patent for the superheterodyne circuit is issued to Major Edwin F. Armstrong. The Society of Motion Picture Engineers (SMPE) is formed. Thomas Edison does live-versus-recorded demonstrations in Carnegie Hall, NYC.
1917	The Scully disk recording lathe is introduced. E. C. Wente of Bell Telephone Laboratories publishes a paper in Physical Review describing a "uniformly sensitive instrument for the absolute measurement of sound intensity" -- the condenser microphone. Albert Einstein posited that light could be amplified and stimulated to form a powerful beam.
1919	The Radio Corporation of America (RCA) is founded. It is owned in part by United Fruit.
1920	RCA begins mass producing commercial radios. Radio quality improves, thus decreasing record sales and the record companies don't like it one bit. (hmmm sounds familiar)
1923	Zenith Radio Corporation founded.
1924	Zenith develops the first portable radio.
1921	The first commercial AM radio broadcast is made by KDKA, Pittsburgh PA.
1925	The research paper of Chester W. Rice and Edward W. Kellogg at General Electric was important in establishing the basic principle of the direct-radiator loudspeaker with a small coil-driven mass-controlled diaphragm in a baffle with a broad midfrequency range of uniform response. Bell Labs develops a moving armature lateral cutting system for electrical recording on disk. Bell Labs introduces electrical amplification. Fidelity increases and record sales rebound. Almost all amplifiers during this period were (by todays standards) of very low power, circuitry using being very simple, typically the (Class A) "single ended triode" circuit topology, usually using directly heated tubes. Victor Orthophonic acoustic phonograph player had a folded exponential horn that was later used as model for the Klipsch speaker of the hi-fi era. This all-acoustic player -- with no electronics -- is considered a leap forward in phonograph design. Within a year, the Orthophonic faced competition from all-electric phonographs with an electromechanical pickup, vacuum-tube amplifier, and moving-coil loudspeaker, such as the Brunswick Panatrope sold by the Brunswick-Balke-Collender Company. The first electrically recorded 78 rpm disks appear. RCA works on the development of ribbon microphones. Zenith creates the first AC-powered radios. Scottish engineer John Logie Baird invents the world's first working television system. He is generally credited with being the first person to produce a live, moving television image in halftones by reflected light.
1926	Joseph A. O'Neill patents iron oxide-coated paper tape.
1927	"The Jazz Singer" is released as the first commercial talking picture, using Vitaphone sound on disks synchronized with film. The Columbia Broadcasting System (CBS) is formed. The Japan Victor Corporation (JVC) is formed as a subsidiary of the Victor Talking Machine Co. Zenith creates the first push-button radios.
1928	Dr. Harold Black at Bell Labs applies for a patent on the principle of negative feedback. It is granted nine years later. Dr. Georg Neumann founds a company in Germany to manufacture his condenser microphones. Its first product is the Model CMV 3. The first three patents for the field-effect transistor principle were registered in Germany by physicist Julius Edgar Lilienfeld. Philo Farnsworth made the world's first working television system with electronic scanning of both the pickup and display devices, which he first demonstrated to news media, televising a motion picture film.
1929	J. D. Seabert of Westinghouse developed a horn-type loudspeaker that directed the sounds of human speech toward the audience better than cone speakers that were intended for the over-all sound including music to fill the entire theater. These "directional baffle" horns had an opening 3 ft. by 4 ft. and were different from small-throat horns. Harry Nyquist publishes the mathematical foundation for the sampling theorem basic to all digital audio processing, the "Nyquist Theorem." The "Blattnerphone" is developed for use as a magnetic recorder using steel tape.
1930s	33-1/3 rpm "Vitrolac" vinyl discs are produced and tape recording cartridges are developed, but due to the depression, leisure electronic goods become luxuries and with the presence of free radio broadcasts, record sales drop.
1931	Bell Labs developed the two-way loudspeaker, called "divided range" for the demonstration by H. A. Frederick of vertically cut records. The high frequencies were reproduced by a small horn with a frequency response of 3000-13,000 hz, and the low frequencies by a 12-inch dynamic cone direct-radiator unit with a frequency response within 5db from 50-10,000 hz. Vladimir Zworykin performs experiments using cathode-ray tube where the scanning electron beam would strike the photoelectric cell from the same side where the optical image was cast. After the achievement of the first promising experimental transmitters, it was decided the new camera tube would be named Iconoscope. Alan Blumlein, working for Electrical and Musical Industries (EMI) in London, in effect patents stereo. His seminal patent discusses the theory of stereo, both describing and picturing in the course of its 70-odd individual claims a coincident crossed-eights miking arrangement and a "45-45" cutting system for stereo disks. Arthur Keller and associates at Bell Labs in New York experiment with a vertical-lateral stereo disk cutter.
1932	The first cardioid ribbon microphone is patented by Dr. Harry F. Olson of RCA, using a field coil instead of a permanent magnet.
1933	FM radio introduced Herman J. Fanger granted patent that described what came to be known as the coaxial speaker, composed of a small high frequency horn with its own diaphragm nested inside or in front of a large cone loudspeaker, based on the variable-area principle that made the center cone light and stiff for high frequencies and the outer cone flexible and highly damped for lower frequencies. William Snow, Harvey Fletcher and J.C. Steinberg of Bell Labs performed the first "sterophonic" demonstration before the National Academy of Sciences and many invited guests at Constitution Hall, Washington. Transmission was over wire lines from the Academy of Music in Philadelphia and three channels were used with microphones respectively at left, center and right of the orchestra stage and loud speakers in similar positions in Constitution Hall. This transmission of music was carried out with special loud speakers developed for the purpose by Dr. Wente and the late A. L. Thuras. A triple-range speaker had been developed for the Constitution Hall demo, adding Western Electric No. 555 driver units as the mid-range speaker to Bell Lab's two-way loudspeaker design. For the low frequency range 40-300 hz, a large moving coil-driven cone diaphragm in a large baffle expanding from a 12-in throat to a 60-inch mouth over a total length of 10 ft was used. This 3-way system was introduced in motion picture theaters as "Wide Range" reproduction. Magnetic recording on steel wire is developed commercially.
1934	E. W. Kellogg granted patent that described an electrostatic speaker composed of many small sections able to radiate sound with out magnets or cones or baffles.
1935	AEG (Germany) exhibits its "Magnetophon" Model K-1 at the Berlin Radio Exposition. BASF prepares the first plastic-based magnetic tapes.
1936	BASF makes the first tape recording of a symphony concert during a visit by the touring London Philharmonic Orchestra. Sir Thomas Beecham conducts Mozart. Dr. H.J. Von Braunmühl and Dr. Walter Weber apply for a patent on the cardioid condenser microphone. The first regular public (i.e. not cable) television broadcasts with a modern level of definition (240 or more lines) were made in England by the BBC from Alexandra Palace, London.
1937	English researcher, Alec Reeves, patented Pulse Code Modulation (PCM)
1938	Benjamin B. Bauer of Shure Bros. engineers a single microphone element to produce a cardioid pickup pattern, called the Unidyne, Model 55. This later becomes the basis for the well known SM57 and SM58 microphones. Under the direction of Dr. Harry Olson, Leslie J. Anderson designs the 44B ribbon bidirectional microphone and the 77B ribbon unidirectional for RCA. RCA develops the first column loudspeaker array.
1939	A handful of TV stations began to broadcast, led by RCA’s New York City station, a direct ancestor of today’s WNBC. Another station, Philco’s WPTZ, broadcast from Philadelphia, a station that evolved into today's KYW. By the end of the year, television was regularly broadcasting in about a dozen cities, and it was possible to buy TV set from any number of companies. Independently, engineers in Germany, Japan and the U.S. discover and develop AC biasing for magnetic recording. Western Electric designs the first motional feedback, vertical-cut disk recording head. Major Armstrong, the inventor of FM radio, makes the first experimental FM broadcast. The first of many attempts is made to define a standard for the VU meter.
1940	Walt Disney's "Fantasia" is released, with eight-track stereophonic sound.
1941	Commercial FM broadcasting begins in the U.S. Arthur Haddy of English Decca devises the first motional feedback, lateral-cut disk recording head, later used to cut their "ffrr" high-fidelity recordings. John Logie Baird develops a 600-line color television system, which unfortunately never got beyond the experimental stage.
1942	The RCA LC-1 loudspeaker is developed as a reference-standard control-room monitor. Dr. Harry Olson patents a single-ribbon cardioid microphone (later developed as the RCA 77D and 77DX), and a "phased-array" directional microphone. The first stereo tape recordings are made by Helmut Kruger at German Radio in Berlin.
1943	Polyvinyl chloride, known as "PVC" or "vinyl," replaces the fragile shellac based discs as the new material for record production. Paul W. Klipsch granted patent for the corner horn speaker. Altec develops their Model 604 coaxial loudspeaker.
1944	Alexander M. Poniatoff forms Ampex Corporation to make electric motors for the military. American and British technical investigators discover the Magnetophon in Luxembourg, France, and other places formerly occupied by the Germans. Stereo Magnetophon Model K-7; K-4 Magnetophons in wide distribution. These investigators begin gathering information about the production of tape recorders and tape, and the information is published by the U.S. Department of Commerce. German patent rights on the technology are seized by the U.S. Alien Property Custodian.
1945	The first commercially produced amplifier with distortion of 0.1% was the LEAK Type 15 "Point One", using KT66 vacuum tubes (valves) connected as triodes, with 26dB feedback over 4 stages including the output transformer. Two Magnetophon tape decks are sent back to the U.S. in pieces in multiple mailbags by Army Signal Corps Major John T. (Jack) Mullin. Three former Armour Research Foundations employees start Magnecord Corporation in Chicago to make a high quality wire recorder.
1946	Webster-Chicago manufactures wire recorders for the home market. Brush Development Corp. builds a semiprofessional tape recorder as its Model BK401 Soundmirror. Minnesota, Mining and Manufacturing Company (3M) introduces Scotch No. 100, a black oxide paper tape. Jack Mullin demonstrates "hi-fi" tape recording with his reconstructed Magnetophon at an Institute of Radio Engineers (IRE) meeting in San Francisco.
1947	The high fidelity industry was born. The Williamson amplifier being a milestone that set the standard (and the dominat topology) for what was to follow, was of the 'push-pull' topology and used negative feedback, coupled with a special design of output transformer, to produce lower levels of distortion than previous designs. Widespread adoption of push pull allowed smaller (and thus cheaper) transformers, combined with more power (typically ~ 10 to 15 watts) sufficient to drive higher quality domestic loudspeakers. John Bardeen, Walter Brattain and William Shockley succeeded in building the first practical point-contact transistor at Bell Labs. Colonel Richard Ranger begins to manufacture his version of a Magnetophon. Bing Crosby and his technical director, Murdo McKenzie, agree to audition tape recorders brought in by Jack Mullin and Richard Ranger. Mullin's is preferred, and he is brought back to record Crosby's Philco radio show. Ampex produces its first tape recorder, the Model 200. Major improvements are made in disk-cutting technology: the Presto 1D, Fairchild 542, and Cook feedback cutters.
1948	Columbia introduces the first 12-inch, 33 1/3 rpm microgroove long-playing "LP" vinyl record. Columbia ensures success by releasing a back catalogue on LP. German physicists Herbert F. Mataré and Heinrich Welker, working at Compagnie des Freins et Signaux Westinghouse in Paris, France applied for a patent on an amplifier based on the minority carrier injection process which they called the "transistron". Scotch types 111 and 112 acetate-base tapes are introduced. Magnecord introduces its PT-6, the first tape recorder in portable cases. Dr. Claude Shannon's paper, Mathematical Theory of Communication, laid the foundations of information theory, and explained that "bits", short for binary digits, could carry information in a digital form. Community antenna television (now called cable television) was started by John Walson and Margaret Walson in the Mahanoy City, Pennsylvania area. Mahanoy City residents had problems receiving the three nearby Philadelphia network stations with local antennas because of the region's surrounding mountains. John Walson erected an antenna on a utility pole on a local mountain top that enabled him to demonstrate the televisions with good broadcasts coming from the three Philadelphia stations. Walson connected the mountain antennae to his appliance store via a cable and modified signal boosters. In June of 1948, John Walson connected the mountain antennae to both his store and several of his customers' homes that were located along the cable path, starting the nation’s first CATV system.
1949	RCA introduces the microgroove 45 rpm, large-hole, 7-inch record and record changer/adaptor. The 7-inch single quickly becomes the standard for the jukebox. Ampex introduces its Model 300 professional studio recorder. Magnecord produces the first U.S.-made stereo tape recorder, employing half-track staggered-head assemblies. A novel amplifier design is described by McIntosh and Gow.
1950	RCA releases records on the 12-inch Columbia format. William Shockley developed a radically different type of solid-state amplifier which became known as the Bipolar Junction "transistor". Although it works on a completely different principle to the point-contact "transistor", this is the device which is most commonly referred to as a "transistor" today. Guitarist Les Paul modifies his Ampex 300 with an extra preview head for "Sound-on-Sound" overdubs. IBM develops a commercial magnetic drum memory. Zenith develops first wired TV remote control – Lazy Bones.
1951	Columbia releases records on the 7-inch RCA format. With 78 rpm discs still available, it takes a decade for a standard playing speed to be determined. The "hot stylus" technique is introduced to disk recording. An "Ultra-Linear" amplifier circuit is proposed by Hafler and Keroes. Pultec introduces the first active program equalizer, the EQP-1. The Germanium transistor is developed at Bell Laboratories.
1952	The first transistorized device, a hearing aid, is sold. Peter J. Baxandall publishes his (much-copied) tone control circuit. Emory Cook presses experimental dual-band left-right "binaural" disks.
1953	The world's first transistor radio was unveiled in Germany at the Düsseldorf Radio Fair by the German firm Intermetall. Arthur Janszen was granted patent for an electrostatic high-frequency speaker. Ampex engineers a 4-track, 35 mm magnetic film system for 20th-Century Fox's Christmas release of "The Robe" in CinemaScope with surround sound. Ampex introduces the first high speed reel-to-reel duplicator as its Model 3200.
1954	Regency and Texas Instruments (TI) develop and market the first all-transistor radio (TR-1). TI markets the first commercial silicon transistor (900 series). Acoustic Research introduced the small AR-1 bookshelf loudspeaker that used the acoustic suspension principle developed by company co-founder Edgar Villchur, which changed the way speakers were designed. Up until that time, speakers of any reasonable quality had to be quite large in size. By using an enclosure with a sealed air cavity behind the speaker cone acting as a spring to damp woofer motion, they were able to make "bookshelf size", less expensive speakers. Although the speaker was inefficient in power consumption compared to ported designs, it had extremely low distortion. RCA sold the first color TV sets. RCA introduces its polydirectional ribbon microphone, the 77DX. EMT (Germany) introduces the electromechanical reverberation plate. Ampex produces its Model 600 portable tape recorder. G. A. Briggs stages a live-versus-recorded demonstration in London's Royal Festival Hall. Westrex introduces their Model 2B motional feedback lateral-cut disk recording head. The first commercial 2-track stereo tapes are released.
1955	Masaru Ibuka, co-founder of the Japanese firm Sony, was visiting the USA when Bell Labs announced the availability of manufacturing licenses, including detailed instructions on on how to manufacture junction transistors. Ibuka obtained special permission from the Japanese Ministry of Finance to pay the $50,000 license fee, and the company introduced their own "pocket" radio under the brand name Sony. (The term "pocket" was a matter of some interpretation, as Sony notoriously had special shirts made with oversized pockets for their salesmen). Ampex develops "Sel-Sync" (Selective Synchronous Recording), making audio overdubbing practical. Zenith develops first wireless TV remote control – Flash-Matic.
1956	Fisher Radio Corporation introduced a milestone device which was described in the owners manual as "the first of its kind in the high fidelity field". It was a small single channel (monophonic) three transistor audio preamplifier. Like the more famous Regency TR-1 radio, the Fisher product was also given the designation TR-1... presumably with the TR referring to TRansistor and 1 being the first model to include the use of such devices. Les Paul makes the first 8-track recordings using the "Sel-Sync" method. Ampex introduced the Ampex VRX-1000, the first commercially successful videotape recorder. Due to its US $50,000 price, the Ampex VRX-1000 could be afforded only by the television networks and the largest individual stations. Zenith introduces the first practical wireless TV remote control, called the Space Command.
1957	Quad ESL marketed as the first full-range electrostatic loudspeaker, designed by Peter Walker and David Williamson, based on Edward W. Kellogg's patent from 1934. Westrex demonstrates the first commercial "45/45" stereo cutter head. The Soviet Union successfully launched Sputnik I, the world's first artificial satellite. Sputnik I was about the size of a basketball, weighed only 183 pounds, and took about 98 minutes to orbit the Earth on its elliptical path. That launch ushered in new political, military, technological, and scientific developments.
1958	The first commercial stereo disk recordings appear. Stefan Kudelski introduces the Nagra III battery-operated transistorized field tape recorder, which with its "Neo-Pilot" sync system becomes the de facto standard of the film industry. Simultaneous with a pair of Soviet physicists, Columbia University scientists Drs. Arthur Schawlow and Charles H. Townes, who earlier had built the maser, a microwave amplifier, outlined the workings to the "laser" – Light Amplification by Stimulated Emission of Radiation.
1959	Jack Kilby at Texas Instruments and Robert Noyce at Fairchild Camera came up with a solution to the problem of large numbers of components, and the integrated circuit was developed. Instead of making transistors one-by-one, several transistors could be made at the same time, on the same piece of semiconductor. Not only transistors, but other electric components such as resistors, capacitors and diodes could be made by the same process with the same materials. EMI fails to renew the Blumlein stereo patent. Hello - anybody home?
1960	Sony Corporation sells the first direct-view portable television.
1961	3M introduces the first 2-track closed-loop capstan-drive recorder, the M-23. Zenith FM stereo system adopted by FCC as industry standard.
1962	The Society of Motion Picture and Television Engineers (SMPTE) sets the standard for the time code format. 3M introduces Scotch 201/202 "Dynarange," a black oxide low-noise mastering tape with a 4 dB improvement in s/n ratio over Scotch 111.
1963	Gerhard Sessler and James West, working at Bell Labs, patent the electret microphone. The Beach Boys contract Sunn Electronics to build the first large full-range sound system for their rock music concert tour. The first communication satellite was developed and launched by a consortium of business and government entities. It was known as Syncom II and achieved an orbit at 22,300 miles over the Atlantic.
1964	Philips introduces its own 30-minute compact audio cassette format for the tape cartridge and offers licenses worldwide, allowing other manufacturers to duplicate the specifications. This standardization of cassette tapes creates a market for an inexpensive and portable solution to reel-to-reel tape. With the price of a blank tape around $3 and a vinyl album at $6 by the end of the 1960s, the record companies start to worry about the recordable cassette affecting their sales. Bill Lear designs the Lear Jet Stereo 8 track cartridge. The first commercial device with an integrated circuit, a hearing aid, is sold. Clive Sinclair started a company called Sinclair Radionics Ltd. that produced a Class D PWM power amplifier known as the X-10, designed by engineer Gordon Edge. To solve the problem of heat in an amplifier, they used a system of 1’s and 0’s in varying lengths. By controlling how long each of the two states remained on (or off), a signal could be produced that, after the appropriate manipulation, would actually produce music. That process became known as Pulse Width Modulation or PWM. The plasma display panel was invented at the University of Illinois by Professors Donald Bitzer, Gene Slottow, and their first graduate student, Robert Willson. NHK Science & Technical Research Laboratories begin research on high definition TV (Hi-Vision).
1965	Robert Moog shows elements of his early music "synthesizers." Eltro (Germany) makes a pitch/tempo shifter, using a rotating head assembly to sample a moving magnetic tape.
1966	The 8-track player is introduced as an option in each of Ford Motor Company's 1966 models. Though the 8-track produces higher quality sound than the cassette tape, it all but disappears from a market looking for convenience and versatility rather than high-end sound reproduction. Integrated circuits are introduced into consumer products, starting with pocket calculators and electronic watches. Ray Dolby develops the Dolby Type A noise reduction system.
1967	Altec-Lansing introduces "Acousta-Voicing," a concept of room equalization utilizing variable multiband filters. Elektra releases the first electronic music recording: Morton Subotnick's Silver Apples of the Moon. The first operational amplifiers are used in professional audio equipment, notably as summing devices for multichannel consoles. The first CES (Consumer Electronics Show) took place in New York City, June 25-28, at the Americana and the New York Hilton hotels. The first solid-state television was introduced at the 1967 show, and exhibitors showed the latest in transistor radios, stereos and small-screen black-and-white TVs (only 16% of U.S. households had a color TV).
1968	CBS releases "Switched-On Bach," Walter (Wendy) Carlos's polyphonic multitracking of Moog's early music synthesizer. Stanford Research Institute researcher Douglas C. Engelbart demonstrated a computer system consisting of a keyboard, keypad, a graphic user interface that used frames on a screen called "windows", a word processor, hypertext that allowed you to point-and-click on a word to produce another window with linked information, and a pointing device called a "mouse" that he had patented five years earlier after introducing it at a computer conference in San Francisco.
1969	Dr. Thomas Stockham begins to experiment with digital tape recording. 3M introduces Scotch 206 and 207 magnetic tape, with a s/n ratio 7 dB better than Scotch 111. Zenith develops Chromacolor, the first black matrix color picture tube. First public demonstration of NHK's Hi-Vision high definition TV technology.
1970	The first digital delay line, the Lexicon Delta-T 101, is introduced and is widely used in sound reinforcement installations. A researcher and audiophile, James T. Russell, at Battelle Memorial Institute in Richland, Wash., was tired of having his records wear out. In the mid-1960s he started to tinker with PCM digital recording, lasers and film media and developed a method to record sound on and play it back from a rectangular 3x5-inch glass plate with photo-sensitive coating, patenting this optical system using a laser to read the digitized music. Philips develops the "VCR" videocassette format. James Fergason, while Associate Director of the Liquid Crystal Institute at Kent State University, invented the first practical uses of liquid crystals by discovering the twisted nematic field effect of liquid crystals which forms the scientific basis of modern LCDs. The twisted nematic field effect in liquid crystals was filed for patent by Hoffmann-LaRoche in Switzerland with Martin Schadt and Wolfgang Helfrich (then working for the Central Research Laboratories) listed as inventors. Hoffmann-La Roche then licensed the invention to the Japanese electronics industry which soon produced the first digital quartz wrist watches with TN-LCDs and numerous other products.
1971	Denon demonstrates 18-bit PCM stereo recording using a helical-scan video recorder. RMS and VCA circuit modules introduced by David Blackmer of dbx. Sony introduces the U-matic system, the world's first commercial videocassette format. The U.S. Congress declares sound recordings worthy of copyright protection and pass the 1971 Sound Recording Amendment to the 1909 Copyright Statute. Though this amendment is proposed largely in response to the record industry's complaints of vinyl bootlegging, the implications of the amendment are applied to the burgeoning recordable cassette market. Record executives complain that teenagers tape and swap their favorite albums, and advocate a tax on blank cassettes to make up for the lost revenue from tape trading. With music sales still growing, the objections to taping are largely unheard. However, by the late 1970s, music sales slide, and the record companies begin an industry-wide campaign to curb home taping.
1972	Electro-Voice and CBS are licensed by Peter Scheiber to produce quadraphonic decoders using his patented matrixes. Quadraphonic sound was one of the earliest consumer offerings in surround sound. Introduced to the American market as the Quad 8 [4-Channel] 8-Track Tape Cartridge. Quad did not remain one format, but was later a myriad of different and largely incompatible formats on different media: quadraphonic could be obtained from vinyl records, eight tracks, and reel-to-reel. Further complicating quadraphonic was the fact that some vinyl systems were discrete, while others were matrix. Henry Kloss's Advent Corp. releases the first large screen projection television for home use called the Advent Video Beam 1000. The first active-matrix liquid crystal display panel was produced in the United States by T. Peter Brody.
1974	D. B. Keele pioneers the design of "constant-directivity" high-frequency horns. The Grateful Dead produce the "Wall of Sound" at the San Francisco Cow Palace, incorporating separate systems for vocals, each of the guitars, piano and drums. DuPont introduces chromium dioxide (CrO2) cassette tape. James Russell succeeded in recording 20 minutes of television programming on a 4x5-inch record, a precursor to DVD, and the technology was demonstrated to representatives of several potential licensees, including Hitachi, Mitsubishi, RCA, Sony and Polygram Philips. Infinity Systems releases the SWAMP amplifier, the first amplifier using PWM technology for the audiophile market. The SWAMP, being the first commercially available Class D amplifier, was a revolutionary product as envisoned by Arnie Nudell and his then partner in Infinity, John Ulrich (now President and chief designer at Spectron Digital Audio Amplifiers). Class-D offers a number of advantages over the established amplifier technologies such as class-AB. A distinct advantage of this technology is the fact that distortion is kept at a set level across all frequencies. Another advantage is the high efficiency (~90%) requiring less cooling, less stringent power-supply constraints and enabling smaller amplifiers to be built.
1975	Sony introduced in the U.S. the Betamax consumer VCR (console only) for $2295 with one-hour 1/2-inch tape cassettes for $15.95. Sony sought to created a standardized format by getting 7 other companies to agree to produce machines that would play the Beta cassettes. Digital tape recording begins to take hold in professional audio studios. Michael Gerzon conceives of and Calrec (England) builds the "Soundfield Microphone," a coincident 4-capsule cluster with matrixed "B-format" outputs and decoded steerable 2- and 4-channel discrete outputs. EMT produces the first digital reverberation unit as its Model 250. Featured on the cover of the January 1975 issue of Popular Electronics was the first personal computer, the Altair 8800. Using the Intel 8080 chip, the Altair was invented by an ex-Air Force officer from Georgia, Ed Roberts, and manufactured by his Albuquerque, N.M., company, MITS.
1976	JVC introduced in Japan the VHS format VCR for $885. Sony introduced a Betamax VCR deck for $1300 and began aggressive advertising claiming that it "can actually videotape something off one channel while you're watching another channel" and "build a library of your favorite shows." The famous consumer video tape cartridge format war starts. Universal Studios and the Walt Disney Company sue Sony and its distributors alleging that because Sony was manufacturing a device that could potentially be used for copyright infringement, they were thus liable for any infringement that was committed by its purchasers. This becomes known as the famous "Betamax case." Dr. Thomas Stockham of Soundstream makes the first 16-bit digital recording in the U.S. at the Santa Fe Opera. It ran at a sampling rate of 50 kHz as opposed to the future audio CD sampling rate of 44.1 kHz. Zenith develops the first extended field lens (EFL) electron gun. Home Box Office (HBO) made history by initiating satellite delivery of programming to cable with the heavyweight boxing match know as “The Thriller From Manila”. The first consumer Direct To Home (DTH) Satellite System was created in a most unusual place – in the garage of Stanford University Professor and former NASA scientist Emeritus H. Taylor Howard. It was a large dish-shaped antenna that he used to pick up programs that cable TV content providers offered for distribution to their subscribers. When Mr. Howard wrote a check for $100 to HBO to pay for movies he had watched, the company returned his check, saying that it dealt only with large cable companies, not individuals. Howard then published a how-to-do-it manual on his system. Soon afterward, with mechanical engineer Bob Taggart, he co-founded Chaparral Communications Inc. of San Jose to produce the parts for the system that he continued to improve. Within six years, Chaparral became a $50 million company.
1977	RCA announced it would sell VHS with 4-hour tapes. Two members of the Stanford Homebrew Computer Club, Steven Wozniak and Steven Jobs, formed a company called Apple Computer Inc., and introduced the first fully assembled personal computer for consumers, the Apple II. The big boost for surround sound was the release of a single movie— Star Wars, with its swooping rear-channel effects. The success of Star Wars inspired theater owners to upgrade their sound equipment to the Dolby Stereo standard, and led to other producers and studios embracing the surround sound format. Pat Robertson launched the first satellite-delivered basic cable service called the Christian Broadcasting Network (CBN), later The Family Channel.
1978	Sony, Philips and PolyGram, led by Philips' researcher Kees Schouhammer Immink and Piet Kramer, head of the company's optical research group, began collaboration on a form of Russell's system, the compact disc, or CD. Instead of mechanical analog recording, compact discs were digital, the music was encoded in binary code onto a five-inch disc covered with a protective clear plastic coating and read by a laser. Sony brings PWM amplifier to market. Pioneer developed the LaserDisc that was first used by General Motors to train Cadillac salesmen. The first EIAJ standard for the use of 14-bit PCM adaptors with VCR decks is embodied in Sony's PCM-1 consumer VCR adaptor. A patent is issued to David Blackmer for an adaptive filter (the basis of dbx Types I and II noise reduction). 3M introduces metal-particle cassette tape. Television began using satellites on March 1, 1978 when the Public Broadcasting Service (PBS) introduced Public Television Satellite Service. Broadcast networks adopted satellite communication as a distribution method from 1978 through 1984.
1979	Cassettes hit the big time with the decline of 8-track players and the introduction of the Sony Walkman. The Walkman revolution coincides with improvement in cassette sound quality and the cassette tape suddenly became the only format that you could have in your home, in your car, and in your pocket. Bell Labs introduced the first single chip DSP (digital signal-processing chip) , the Mac 4 Microprocessor. Design efforts were begun by NHK Science and Technical Research Laboratories to create the MUSE system. This was the first successful HDTV technology and used an analog 1035-line interlaced resolution.
1980s	With the introduction of the CD, the '80s become the most explosive boom period in recorded audio history, as consumers replace their vinyl collections. Within three years of the CD's arrival in the marketplace, the electronics industry sells one million CD players. By contrast, it took 11 years for color television manufacturers to sell one million units. The video tape format war continues. Neither format really took off, though, until consumers could buy video tapes of movies — or at least rent them. And while VHS had an advantage of number of titles, it was one area that VHS appeared to have a virtual monopoly: porn. While porn production exploded in the early 1980s, virtually all of it was released on VHS and not Beta. Within a few years, what had been a fairly even race, turned into a romp, with VHS running away into the lead, forcing Sony to eventually sell VHS machines. The Recording Industry Association of America (RIAA), the record industry's lobbying and trade organization, continues its fight for taxes on blank tapes and legislators eventually grant the music labels a portion of every blank tape sale.
1980	The world standard for optical digital audio compact disc (CD) is established. Pioneer began selling home LaserDisc players. 3M, Mitsubishi, Sony and Studer each introduces a multitrack digital recorder. EMT introduces its Model 450 hard-disk digital recorder. The first stand-alone, complete DSPs -- the NEC µPD7720 and AT&T DSP1 -- were presented at the IEEE International Solid-State Circuits Conference '80. Both processors were inspired by the research in PSTN telecommunications.
1981	Philips demonstrates the Compact Disc (CD). MIDI is standardized as the universal synthesizer interface. IBM introduces the IBM Personal Computer model 51510. The IBM PC used Intel's new 8088 chip, a wealth of off-the-shelf computing technology and, most importantly, an operating system called MS-DOS, provided by Bill Gates and Paul Allen, who had by this time founded a software company called Microsoft. IBM, the world's largest computer maker, quickly proved that there was a consumer market – at least for mainstream businesses – for the personal computer. The “big-dish” C-Band satellite market began to take off. System sales soared as hardware prices fell, and the idea of a practical DBS system was beginning to take shape. As the hardware price came down, more people looked to the multiple-channel capabilities of satellite TV as an alternative to cable. The programming was free during these years. People made a one-time purchase of a system and received more than 100 channels, including every basic and premium cable service…free!
1982	Record companies announce a worldwide standard that ensures that all CDs will play on all CD players. Billy Joel's 52nd Street, released in Japan, becomes the first CD released in the world. Sony releases the first CD player, the Model CDP-101. Dolby Laboratories introduces surround sound for home use. Sony introduces the PCM-F1, intended for the consumer market, the first 14- and 16-bit digital adaptor for VCRs. It is eagerly snapped up by professionals, sparking the digital revolution in recording equipment.
1983	The first DSP produced by Texas Instruments (TI), the TMS32010 is presented. Another successful design was the Motorola 56000. Fiber-optic cable is used for long-distance digital audio transmission, linking New York and Washington, D.C. Apple unveiled the Lisa, which used a graphical user interface (GUI), developed originally at Xerox Corp.'s Palo Alto Research Center (PARC). Instead of a keyboard and arcane typed commands, Engelbart's mouse was used to move a cursor around the screen. Users placed the cursor at on-screen icons or selected items in pull-down menus that represented programs, functions and commands, and then clicked a button on the mouse to activate particular actions, a far more user-friendly way to control computer activities. A start-up company called Compaq Computer Corporation sold the first IBM-compatible portable. The Compaq Portable was the first 100% compatible IBM computer clone. Compaq was founded by Rod Canion, Jim Harris and Bill Murto, three senior managers who left Texas Instruments and invested $1,000 each to form their own company. Sketched on a paper place mat in a Houston pie shop, the first product was a portable personal computer able to run all of the software being developed then for the IBM PC. The grandfather of serious Class D, Brian Attwood, published what's probably still the single most famous paper on Class D amplification "Design Parameters Important for the Optimization of Very-High-Fidelity PWM (Class D) Audio Amplifiers".
1984	The Supreme Court of the United States ruled in the famous "Betamax case" that the making of individual copies of complete television shows for purposes of time-shifting does not constitute copyright infringement, but is fair use. The Court also ruled that the manufacturers of home video recording devices, such as Betamax or other VCRs (referred to as VTRs in the case), cannot be liable for infringement. The case was a boon to the home video market as it created a legal safe haven for the technology, which also significantly benefited the entertainment industry through the sale of pre-recorded movies. Apple's so-called point-and-click technology came to the masses via the Apple Macintosh. Microsoft brought the GUI to IBM-compatible machines with the introduction of its Windows operating system. Mark Sandler's paper, "Towards A Digital Power Amplifier," delivered at the AES Convention, generated more academic interest in digital (PCM-PWM) amplification. Dr. Sandler became a professor in the EE department at King's College London, where he and his students have delivered over a dozen papers on the subject. Joining his research was the Technical University of Denmark (DTU) who targeted this technical area for intensive research with great results. At least three DTU students turned their university research into successful products. Zenith/dbx MTS stereo sound system chosen as industry standard for broadcast TV. Several cable programming providers lobbied the government, which subsequently introduced the 1984 Cable Act, allowing them to encrypt (convert into code) their satellite feeds. Scrambling systems were developed so their signals were no longer broadcast “in the clear” for everyone with a satellite dish to pick up without any payment to the program developers. Free dish satellite TV programming was outlawed and the satellite sales industry dramatically dropped.
1985	Dolby introduces the "SR" Spectral Recording system. The compact disk-digital audio technology was extended for computer storage. This was called a CD-ROM (compact disk-read only memory) and later became a standard ECMA-119, which specifies the CD-ROM physical format. The logical format of the CD-ROM is specified in the ISO standard 9660 and allows data access through file name and directories. Amiga 1000 launched. The first real multimedia computer with ground breaking A/V facilities: 4096 colour graphics, 4 channel 8 bit sound, and a proper pre-emptive multitasking OS.
1986	A small group of music lovers, frustrated with the harsh, lifeless, irritating sound they were getting from CD audio, modified early Philips CD players by including new analog "brick wall" filters utilizing Mills resistors, Teflon and polystyrene capacitors and digital signal re-clocking. These improvements led to a whole new analog section with new digital to analog converters (DACs), op-amps and power supplies on a Teflon circuit board. The design team, which later became Theta Digital Corporation, showed that with these modifications, digital had potential. During CES 1986, California Audio Labs introduces the world’s first audiophile, tube-powered, analog-output-stage CD player, the original CAL Tempest I. The first digital consoles appear. Dr. Gunther Theile describes a novel stereo "sphere microphone." The European Commission proposes the HD-MAC HDTV standard. The signal created by HD-MAC was an analog signal but was multiplexed with digital sound. One of the downfalls of the system was the fact that it was always uncompressed and required up to 36 MHz per transmission. The system did use a 1250-line, 16:9 aspect ratio image, but with the need for a brand new tuner HD-MAC did not get support from the broadcasters.
1987	The Digital Audio Tape (DAT) is introduced and meets with immediate resistance from composers and music publishers fearful of piracy due to the DAT's superior sound quality and capacity for near-perfect duplication. The RIAA immediately argues for the "serial copy management system" (SCMS, pronounced scums) to be placed within the DAT recorder to prohibit duplication. Even after SCMS is included on every DAT recorder exported to the U.S., publishers and composers argue for royalties on each DAT machine or tape sold in order to compensate for possible home taping. The continuing debate slackens record industry support for the format. As record labels begin to see the DAT as not viable, they choose not to market or produce pre-recorded DATs. In the absence of pre-recorded tape, the consumer will not buy the recorder. Without recorder sales, there's no market for pre-recorded tape. The DAT does not break into the consumer market. The FCC established an Advisory Committee on Advanced Television Service. Their main role was to decide which standard was to be used for future digital televisions. Of the 23 different systems that were proposed, the Advanced Television Systems Committee chose the new digital television standard that we use today. The ATSC standard (1920x1080 pixels, 16:9) has more than six times the resolution of the earlier NTSC standard (480 displayable lines, 4:3). The prestigious Fraunhofer Institut research center began researching high quality, low bit-rate audio coding, a project code-named EUREKA. The Fraunhofer research was led by Karlheinz Brandenburg often called the "father of MP3". AdLib, Inc. creates the first high volume soundcard (the AdLib Music Synthesizer Card) for computers using FM synthesis (chip by Yamaha YM3812). Creative Technology releases the Creative Music System ("C/MS"), also one of the first add-on soundcards for personal computers. Digidesign markets "Sound Tools," a Macintosh-based digital workstation using DAT as its source and storage medium. Zenith introduces the first flat-screen high-resolution color picture tube. Dr. Larry Hornbeck of Texas Instruments Inc. develops the Digital Micromirror Device, or DMD: an optical semiconductor capable of steering photons with unparalleled accuracy. This digital micro-mirror - greatly refined - is the basis of modern DLP (Digital Light Processing) technology.
1988	The CD surpasses the LP in sales. Recordable CDs are demonstrated. Moving Pictures Expert Group (MPEG) working group is formed. Theta Digital released the DS Pre, which was the first DSP-based outboard digital to analog converter (DAC). This unit, which utilized 16x over sampling, was an instant success due to its dramatic superiority over the then state-of-the-art solid state and vacuum tube CD players. The second generation of DSPs began to spread. Members of this generation were for example the AT&T DSP16A or the Motorola DSP56001. Sharp Electronics develops the 14" TFT color liquid crystal display which heralds the new LCD age.
1989	Fraunhofer received a German patent for MP3 - Moving Picture Experts Group-1, Audio Layer III, a standard for audio compression that makes any digital music file smaller with little or no loss of sound quality. The first PC soundcard from Creative Technologies bearing the Sound Blaster name appeared. Wadia Digial entered the high-end audio scene with their revolutionary Wadia 2000 Digital Decoding Computer, another DSP-based outboard DAC. The four-box 2000 broke new ground in several areas, including a radically different digital filter with 64x over sampling, a jitter-attenuating reclocking circuit, the first consumer use of glass-fiber optical interface, and a chassis machined from a solid block of aluminum.
1990	Turtle Beach developed the first PC sound card to use high quality A/D and D/A, a high quality synthesizer from eMu, and an onboard DSP chip. This product was called "MultiSound" and it went on to became Turtle Beach's claim to fame in the PC industry, winning every magazine's "Best of" awards hands down. The MultiSound product took Turtle Beach from the insular music hobbyist and pro audio markets into the "big leagues" of the PC market. Dolby proposes a 5-channel surround-sound scheme for home theater systems. The write-once CD-R becomes a commercial reality. Microsoft spent $10 million to promote Windows v3.0, considered the first version of Windows ready for prime time. Amiga CDTV - An Amiga with a built in CDROM drive and housed in a CE style case and came with a remote control. A commercial failure, but an early attempt at a convergence product.
1991	MPEG-1 standard published. Hauppauge introduces their WinTV "TV on your PC" ISA-bus based PC tuner card. For the first time a PC user could watch television in a resizable window on their PC screen. Wolfgang Ahnert presents, in a binaural simulation, the first digitally enhanced modeling of an acoustic space. Alesis unveils the ADAT, the first "affordable" digital multitrack recorder. Apple debuts the "QuickTime" multimedia format. Sharp Electronics introduces 8.6" wall-mount LCD color TVs and 8.4" color TFT LCD for notebook computers. Four large cable companies launched a Direct Broadcast Satellite (DBS) system called Primestar. Primestar was a medium-powered DBS-style system utilizing FSS technoloy that used a larger 3-foot (91 cm) satellite dish to receive signals (as most FSS satellites require).
1992	The Philips DCC and Sony's MiniDisc portable player system, using digital audio data-reduction, are offered to consumers as record/play hardware and software. The Audio Home Recording Act of 1992 requires manufacturers of digital recorders to pay a 2 percent royalty rate to copyright holders to compensate for the ease of piracy that digital recording allows. In addition, digital audio recording devices are required to include a device that prohibits serial copying. I believe this is referring to the SCMS technology that was used in DAT recorders. Cinema surround sound became digital with the introduction of Dolby Digital Surround (originally known as Dolby AC-3, short for audio coding 3). This system still encodes the audio information on a film's optical tracks, but in digital format instead of in analog fashion. Dolby Digital also introduced more channels—a 5.1 configuration with left front, center front, right front, left surround, right surround, and a separate low frequency effects (LFE) channel for deep bass.
1993	The music industry files one of the first lawsuits challenging digital technology. Frank Music Corp. files a suit against the online service CompuServe on behalf of the more than 140 music publishers of the Harry Fox Agency. The suit argues that CompuServe's music forum allows users to download music files without the consent of the copyright owners. Digital HDTV Grand Alliance was formed in May of 1993 under the auspices of the FCC and was tasked with producing a single set of standards that would allow HDTV transmission to be phased into use in the United States. Members of the Grand Alliance included General Instrument, Zenith, Sarnoff Labs (RCA), the Massachusetts Institute of Technology (MIT) and AT&T Labs and Philips. Digital HDTV Grand Alliance selected Dolby AC-3 to provide digital surround sound for the emerging technology of digital television. The Digital Theater Systems company introduced the competing DTS surround sound technology. Like Dolby Digital, DTS is a digital 5.1-channel system. Unlike Dolby Digital, however, DTS records the audio channels on CD, which on playback is synchronized to the film's time code. The first DTS movie was 1993's Jurassic Park.
1994	The appearance of cheap DSP chips and the ensuing popularization of DSP created one of the turning points in Class D amplifier history. A result of this was a large number of DSP people dreaming of the "digital amplifier" with a DSP supplying the PWM and "a switching back-end to turn it into power". Another turning point in Class D amplifier history was when Harris released their HIP4080/4081 gate drive chips. It allowed a large number of experimenters to get Class D amplifiers working without getting into the nitty gritty of gate drive. Suddenly these chips and their attentdant evaluation board demonstrated that nearly any working class D amplifier actually sounded quite good. Divx, originally known as Zoom TV, was conceived by prominent Los Angeles entertainment law firm Ziffren, Brittenham, Branca and Fischer. They teamed up with Circuit City Stores, the largest consumer electronics retailer in the U.S. at the time, to develop the idea into a marketable product. Divx (the name was derived from the company's name of Digital Video Express L.P.) was based on DVD-V, and boasted high-quality MPEG-2 digital video and Dolby Digital surround sound. Divx was a rental system, perhaps the most sophisticated ever offered to the public, that allowed near video-on-demand, with no late fees and the availability of many "hot new release" rental titles day and date with their VHS equivalents. The Hughes DIRECTV Satellite System (DSS), the first national high-powered upper Ku-band DBS system, was launched providing great pictures and stereo sound on 150-200 video and audio channels. The small digital satellite TV dish era began in a serious way.
1995	RealNetworks successfully launches the first major streaming audio service. In comparison to the long wait associated with downloading a music file, streaming audio becomes highly popular, despite initial poor audio quality. The Frank Music vs. CompuServe suit is settled, when CompuServe pays the Harry Fox Agency more than $600 per song allegedly infringed. The DVD Forum was founded under the original name DVD Consortium. Ten companies founded the organization. All companies in the DVD Consortium agreed to DVD standards. The first "solid-state" audio recorder, the Nagra ARES-C, is introduced. It is a battery-operated field unit recording on PCMCIA cards using MPEG-2 audio compression. The next major Microsoft Windows upgrade arrived with Windows 95, which was backed with a $300 million ad campaign; within a year, the company had shipped 30 million copies. Ti Khan and Steve Scherf create CDDB (which stands for Compact Disc Database), which is a database for software applications to look up audio CD (compact disc) information over the Internet. The third generation DSPs added application-specific units with instructions in the data path, or sometimes as coprocessors. Some chips, like the Motorola MC68356, even included more than one processor core to work in parallel. Other powerful 3rd gen DSPs were the TI TMS320C541 or the TMS320C80.
1996	United States patent issued for MP3. DVD-Video players started selling in Japan. The Verity Group in Britain formed New Transducers Ltd, now known as the NXT company, to develop the Distributed-Mode Loudspeaker (DML) based on the patent by Dr. Ken Heron of Britain's Defense Evaluation & Research Agency (DERA). Chromatic Research develops Mpact1 MPEG1/2 decoder chip that could output a progressive RGB image from an interlaced DVD. Gateway 2000 produced a combination PC, TV tuner, and 36-inch CRT monitor called the Gateway Destination. Record labels begin to add multimedia files to new releases, calling them "enhanced CDs." Experimental digital recordings are made at 24 bits and 96 kHz. FCC adopts Zenith digital TV transmission technology. Texas Instrument's first commercial DLP systems are shipped to InFocus, nView and Proxima. Echostar’s Dish Network went online in the US and has gone on to similar success as DirecTV’s primary competitor.
1997	Developer Tomislav Uzelac of Advanced Multimedia Products invented the AMP MP3 Playback Engine, the first successful MP3 player. San Diego's MP3.com was founded in November by Michael Robertson. Capitol Records announces intentions to offer the single from the new Duran Duran album in downloadable form on the Internet one month before the album's release to retail stores. Capitol sees this as an exploration of the marketing capacity of the Internet; however retail stores see this as a threat to their sales. Capitol concedes and agrees to delay the release of the single on the Internet to coincide with the album's release in stores. In August, the Artist Formerly Known as Prince announces that his next album will only be available via the Internet or an 800 number. The move is a symbolic statement that in the Internet world, the artist is freed from the economic shackles of the record labels and record stores. He sells 100,000 albums without the aid of a record label, but the experiment highlighted the difficulties of trying to create a new distribution service from scratch. DVD-Video players started selling in the U.S. The first progressive scan DVD player on a PCI card, called the DVD Max, is sold. Lars Risbo and Niels Anderskouv, a couple of the DTU graduates that worked with Dr. Mark Sandler, teamed up to found Toccata Technology (acquired by Texas Instruments in 2000). They develop a PCM (pulse-code modulation)-to-PWM (pulse-width modulation) technique that applies the digital signal directly to the amplifier's output stage, in effect using the amplifier as a digital/analog converter. TiVo, Inc. was incorporated as "Teleworld, Inc." by Jim Barton and Mike Ramsay, veterans of Silicon Graphics and Time Warner's Full Service Network digital video system. Originally intending to create a home network device, they later developed the idea to record digitized video on a hard disk. Philips Electronics releases the DVX8000 multimedia home theater, claiming to enable a convergence of DVD, CD audio, television and PC applications in one living-room appliance.
1998	Two university students, Justin Frankel and Dmitry Boldyrev ported AMP to Windows and created Winamp. Winamp became a free MP3 music player boosting the success of MP3. Fraunhofer started to enforce their patent rights. All developers of MP3 encoders or rippers and decoders/players now have to pay a licensing fee to Fraunhofer. The RIAA accuses three unnamed Internet pirates of posting audio files from hundreds of recording artists, thus allowing anyone to download the audio files freely. The accused pirates settle with the RIAA and in exchange for agreeing not to post again, the RIAA waives their fines, which totaled well over $1 million per violation. The DVD Forum, after lengthy consultations with the music industry, released a draft DVD-Audio standard. DVD-Audio is a digital format for delivering very high-fidelity audio content on a DVD and offers many possible configurations of audio channels, ranging from single-channel mono to 5.1-channel surround sound, at various sampling frequencies and sample rates. (The ".1" denotes a Low Frequency Effects channel (LFE) for bass and/or special audio effects.) Benwin marketed the first DML flat panel loudspeakers. Chromatic Research develops Mpact2, the new and improved 2nd generation MPEG1/2 decoder chip, which was used in the popular 3DFusion DVD card sold by Digital Connection. Compaq Computer sells the Compaq PC Theater System. Christy Warren gives birth to the HTPC after writing a positive review of the 3DFusion DVD card and creating the acronym "HTPC" for home theater personal computers in a USENET Internet newsgroup. EQUIBIT technology is developed jointly by NAD London and Denmark's Toccata Technology. The TACT Millennium, based on EQUIBIT technology, is the first true digital audio power amplifier because it employs a PWM (pulse-width modulation) amplification stage to amplify a digital signal and couple it directly to the loudspeaker without converting it to the analog domain. Divx (officially announced in September 1997) was released to test markets June of 1998, and nationwide a few months after that. Divx was hampered by a scant title selection, only 2 player models (both produced by Thomson), and lack of retail distribution (many Circuit City competitors refused to carry a product that it owned two-thirds of). The idea of a system designed for metered disc viewing enraged many film buffs and home theater hobbyists, and a virulent anti-Divx campaign erupted on the Internet. Teleworld began the first public trials of the TiVo device and service in the San Francisco Bay area. The first MP3 player, the MPMan F10, manufactured by Korea's Saehan Information Systems, was launched at CeBIT, and went on sale in the Summer through Eiger Labs for $250. The player featured 32MB of flash memory (which could be upgraded to 64MB via mail-in scheme), connected to PCs via parallel port, and had a small LCD for playback info. Following the MPMan's release, Diamond Multimedia unleashed its Rio PMP300, which received a warmer reception and all-but eclipsed the F10's status as "first" amongst players, likely due to the company's well-known (and groundbreaking) legal battle against the RIAA. The RIAA filed an application for a Temporary Restraining Order to prevent the sale of the Rio player in the Central District Court of California, claiming the player violated the 1992 Audio Home Recording Act. The case brings to light the fact that the wording of the act limits the requirement to digital audio recording devices that can accept input from a consumer-electronics device such as a stereo. The Rio, designed to record audio from a computer, which is not categorized as consumer-electronic, is exempted.
1999	A record company called SubPop is the first to distribute music tracks in the MP3 format. 18-year-old Northeastern University dropout named Shawn Fanning created a program that allowed consumers to trade MP3 files stored on their own local hard drives with other music files stored on other consumers' hard drives. This file-swapping program was called Napster, a nickname Fanning got because of the way he tucked his nappy hair under a baseball cap. The RIAA sues Napster for alleged copyright infringement. The DVD Forum released the final version 1.0 of the DVD-Audio specification. Another DTU student, Karsten Nielsen, completed his PhD, while working for Bang & Olufsen (B&O). For the first time in the 75-year history of B&O, a private person (Karsten Nielsen) was given joint ownership of a new venture called Bang & Olufsen ICEpower a/s. The ICEpower team develops both analog and digital PWM amplifier modules for OEM audio manufactures. Software DVD decoding becomes viable because of the accelerated increase in CPU performance. Alan Gouger and David Bott worked on the AV Science Web site to take Home Theater, and what Alan (AV Science) offers, to the Internet. David came up with the idea of “AV Science Q&A” where people would ask questions on the topic of Home Theater and receive answers from Alan and David. As Home Theater started to catch on and grow, the site did the same. It got to a point where it took on a life of its own and they created the AVS Forum. Many feel it was when AVS and Mark Rejhon opened the Home Theater Computers (HTPC) sub-forum that the HTPC became a truly viable option and this may have been the single most important event in the history of the HTPC. John Adcock and a group of volunteer programmers develop DScaler, the first open source software program providing video scaling and deinterlacing utilizing an advanced 3:2 pulldown algorithm. Shortly after Divx's one-year anniversary, Circuit City chief Dick Sharp had had enough. On June 16th, he ordered the plug pulled on Divx development and marketing. Prices on players were slashed to where they were substantially below their DVD-only equivalents, while disc prices dropped from $4.49 to $1.99, and then to 99 cents. Discs still unsold at Circuit City stores at the end of the summer 1999 were destroyed. Sharp Electronics introduces an LCD TV with a large 20" high quality screen. The first DLP projector specifically engineered for home theater is shown by DreamVision. DLP Cinema projector technology is publicly demonstrated for the first time on two screens in Los Angeles and New York for the release of Lucasfilm's Star Wars: Episode I - The Phantom Menace. Primestar sold its assets to Hughes and switched off. Mike Ramsay announced to his company, Teleworld, that the first version of the TiVo digital video recorder would ship on March 31st, despite an estimated four to five months of work remaining to complete the device. Because March 31, 1999 was a Blue Moon, the engineering staff code named this first version of the TiVo DVR "Blue Moon." Teleworld, Inc. renamed themselves to TiVo, Inc.
2000	The first DVD-Audio players enter the market. Sony and Philips Electronics, the same companies that created the CD, introduce Super Audio CD (SACD), another optical audio disc format aimed at providing much higher fidelity digital audio reproduction than the compact disc. SACD goes into a format war with DVD-Audio and neither side makes significant progress toward acquiring consumer acceptance. VM Labs introduces their Nuon technology that enhances movie playback and navigation and adds features for gaming on the DVD platform. Unfortunately, VM Labs filed for bankruptcy in 2001 and the format seems to have died off. The first CD players capable of playing MP3-encoded CDs are available and the first stereo audio component hard disk MP3 jukeboxes are introduced. The band Metallica and the rapper Dr. Dre sue Napster for alleged copyright infringement. AV Science is the first company to offer an OEM turnkey HTPC. Philips Electronics introduced the DSR6000, the first DirecTV receiver with a TiVo DVR integrated. This new device, nicknamed the "DirecTiVo," stored digital signals sent from DIRECTV directly onto TiVo's hard disk. Telemann introduces the HiPix, the first add-on PC card that allows you to decode high definition Digital Television (DTV) and analog (standard NTSC) signals, and view them on an HD ready television, analog television, or PC monitor. The original software was full of bugs and limitations, but later a group of AVS Forum members took over the development and made significant improvements. The on-screen controller still has the AVS logo displayed.
2001	Apple introduced its stylish iPod MP3 player series, which included a model with a 20-GB hard drive – enough to hold nearly 5,000 songs – in a player smaller than a deck of playing cards. Along with the iPod was Apple's iTunes online music store, which offered individual song downloads for 99 cents each or entire albums at $9.99. After years of legal battles, Napster is ordered to remove all copyrighted material from its network, and the service shuts down. The company then strikes a deal with the National Music Publisher's Association to pay $26 million for past abuses and $10 million toward future royalties. Peer-to-peer file-sharing services, such as Kazaa, Morpheus and Grokster spring up; however, in contrast to Napster, these services avoid the use of a centralized server. The RIAA sues Kazaa, Morpheus, and Grokster for copyright infringement. Motorola announced they have developed a digital audio amplification process, dubbed Symphony. Amplifiers will do the Symphony processing in a Digital Signal Processor (DSP) program using Motorola's 56300 DSP family. Motorola plans to integrate Symphony processing into future DSPs, much like Dolby Digital, HDCD, AC3, and other algorithms are integrated now. A vendor need only add output power transistors and an output filter to get a high power and high efficiency digital amplifier. While working for Philips, Bruno Putzeys designed several generations of discrete Class D amps, culminating in UcD (Universal Class D), which differs from other Class D concepts by putting the output filter into the amplifier’s feedback loop which results in making the amplifier frequency response independent of the attached load. The UcD concept has other benefits, such as an excellent impulse response and slew-rate irrespective of the attached loudspeaker. Six days after the official cutoff date of July 1, 2001, all Divx accounts expired, and Divx became just a fond memory to its legions of users, bringing one of the most colorful eras in the history of home video to an end. Korea's Samsung Electronics develops 40" LCD panel for TV. Sharp Electronics announces the first 16:9 DLP projector, greatly anticipated by home theater enthusiasts. HDNet was launched by Dallas Mavericks owner and billionaire Mark Cuban and Phillip Garvin from studios in Colorado. HDNet is a general interest television channel in the US, broadcasting exclusively in high-definition format, and available via cable and satellite television. "HD on mainstream cable and satellite would not be where it is today without the crazy billionaire out there subsidizing uber expensive HD rigs and traveling around taping anything and everything in HD." (quote from AVS Forum member "cinemascope")
2002	Microsoft releases Windows XP Media Center Edition (MCE), a version of Windows XP designed to serve as a home-entertainment hub. This first release was based directly on Windows XP Professional and was only available from Tier 1 computer manufacturers (HP, Dell, et al). MCE is distinguished from other editions of Windows XP by an exclusive preinstalled application, Media Center, which provides a large-font ("10-foot"), remotely accessible interface for TV viewing on the computer as well as recording and playback, DVD playback, video playback, photo viewing, and music playback. Annual world production of DVD-Video discs surpassed VHS cassettes. Blue and red laser high-definition DVD recording standards are announced. High-Definition Multimedia Interface (HDMI) digital video connector format is announced. Blu-ray Disc Founders (BDF) organisation formed to promote their HD disc system over rival blue-laser technology from the DVD Forum. Samsung Electronics develops first 46" and 54" LCD panels for TV.
2003	Apple Computer launches the most successful online music store to date. In its first year, Apple sells 70 million songs at $0.99 per song, creating nearly $70 million in legal Internet music sales. Questions remain as to how the new market for legal downloading will affect the sales of physical CDs and whether it will redefine the basic unit of music consumption. U.S. District Judge Stephen V. Wilson rules that file-sharing networks do not violate copyright law because the Morpheus and Grokster networks cannot be held liable for illegal activity of Internet pirates that may take place within their network. DVD-Video rentals increased 51.2% and VHS rentals dropped 29% from the previous year; DVD-Video sales increased 42.2% to $12.1 billion and VHS sales dropped 34.8% to $2.4 billion. The DVD Forum voted to support HD DVD as the high definition successor of the standard DVD. HD DVD discs support audio encoding in up to 24-bit/192 kHz for two channels, or up to eight channels of up to 24-bit/96 kHz encoding. The HD DVD format supports a wide variety of video resolutions, including all video resolutions supported by the DVD-Video standard, and up to HDTV formats such as 720p, 1080i and 1080p. DVD-Audio recording specifications are announced. Samsung Electronics develops 57" LCD panel for full HDTV.
2004	Microsoft ships Windows XP Media Center Edition 2005. This is the first edition of MCE available to non-Tier 1 system builders, amongst the other things includes support for Media Center Extenders, and CD/DVD-Video burning support. The first HD car radio was sold Jan. 5 in Cedar Rapids, Iowa, according to the iBiquity Digital Corp. press release, "the biggest revolution in radio since the advent of FM broadcasting more than fifty years ago." Blu-ray founders rename organization to Blu-ray Disc Association (BDA). Choosing a new name opens the way to allow other firms to join, something a little tricky to do if the organization nominally contains only founder-members. In 2004, Cablevision's Voom service went online, specifically catering to the emerging market of HDTV owners and aficionados, but folded in April 2005, with the service’s “exclusive” high-definition channels currently being migrated to the Dish Network system.
2005	The first PCs with dual processors become available. NHK of Japan demos "Super Hi-Vision" TV running at 7680 x 4320 — 16 times the resolution of 1080i. The demo involved a live feed from a couple of custom built cameras based around 8 megapixel CCDs, with their 24Gbps signal being chopped into 16 HD signals and sent 161 miles over a fiber optic network to the the demo site at the 2005 World Exposition in Aichi Japan. Samsung Electronics develops the world's largest 82" full HDTV TFT-LCD panel.
2006	Toshiba released their first HD DVD player in Japan at ¥110,000 ($934). HD DVD was later released in United States, with players priced at $499 and $799. Samsung Electronics unveils the first Blu-ray Disc player. The $1,000 BD-P1000 will play video content from BD discs at 720p or 1080i which the player will output to HDTV using High Definition Multimedia Interface (HDMI). A much anticipated battle, or ‘format war’, is in progress similar to that seen in the 1980’s between VHS and Betamax. This time around the same companies have fallen into the same camps and war is ensuing between Blu-ray and HD DVD technology. VidaBox announced the first Dual HD player / media center capable of playing back both Blu-ray and HD DVD disc formats. Digital TVs surpass sales of analog TVs to dealers for the first time. The TiVo Series3 was introduced. This revision represented an evolutionary step in the TiVo service, adding the capability to record high definition television and digital cable content utilizing CableCARD technology.
2007	Microsoft released Windows Vista, their graphical operating systems used on personal computers, worldwide to the general public. Windows Vista contains hundreds of new features; some of the most significant include an updated graphical user interface and visual style dubbed Windows Aero, improved searching features, new multimedia creation, and completely redesigned networking, audio, print, and display sub-systems. Vista also aims to increase the level of communication between machines on a home network using peer-to-peer technology, making it easier to share files and digital media between computers and devices. Windows Media Center, which was previously exclusively bundled as a separate version of Windows XP, known as Windows XP Media Center Edition, has been incorporated into the Home Premium and Ultimate editions of Windows Vista. LG Electronics announced the release of the first player to market able to play movies from both High Definition Formats. However, It is not able to utilize the interactive menu's and features HDi of the HD DVD format. Samsung Group announced their Duo HD player, a hybrid Blu-ray and HD DVD standalone set-top player. It will fully support both Blu-ray and HD DVD disc formats and their interactive technologies, BD-Java and HDi. This is the first player announced that fully supports the specs of both formats. The first case between the RIAA and someone accused of copyright infringement goes to trial. The jury in Capitol Records v. Thomas concluded 30-year-old Jammie Thomas infringed recording industry copyrights on 24 music tracks and awarded $9,250 in statutory damages per song, after finding that the infringement was "willful." The grand total was $222,000 in damages.
2008	The Blu-ray and HD DVD format war is over and Blu-ray is declared the winner. After Wal-Mart stores said they would no longer sell HD DVD players, Toshiba, the main backer of HD DVD high-definition disc technology, declared that the company will no longer continue to manufacture HD DVD players.

Original sources for this chronology include Callie Taintor's "Chronology: Technology and the Music Industry", which is part of Michael Kirk's wonderful film "The Way Music Died." Ms. Taintor also references: Steve Schoenherr's Recording Technology History, and The BBC's "The History of Vinyl".

additional sources include:
The Audio Engineering Society's (AES) An Audio Timeline, The Museum of Sound Recording's History of Sound, Jack Ward's Transistor Museum, Steven E. Schoenherr's Loudspeaker History, Mary Bellis' article "History of MP3", CEA: Digital America 2006 History and Chronology, Mike McGann's "The Unofficial History of Home Theater, Parts I, II and III, and an article by Christopher Jones titled, "MP3 Overview". I'd also like to thank the folks on the AVS Forum (Home Theater Computers) for their help.

So, as you can see, we've gone from wax cylinders to vinyl and magnetic tape to CD to Blu-ray and HD DVD. I'm still missing some details I may fill in later, like some more background information about DACs and Class D amplifiers and other digital amps. I know some of the breakthrough DACs include Analog Device's AD1860, Burr-Brown's PCM63 and PCM1702/1704, Philip's TDA1541 and something called the Ultra Analogue DAC, but I can't seem to find any dates. I haven't been able to find any good sources that provide a more historical perspective on Class D and digital technology, either. If you discover any mistakes or have any additional information, please leave a comment!

Update 5/3/07: I received some very interesting information about the history of Class D amplifiers from Bruno Putzeys and added them to the timeline. Thanks Bruno!

Update 9/17/07: Added new information thanks to several suggestions from this AVSForum thread .

Update 4/8/08: Added information about the first sound recording (1860) after reading this NYTimes article . I also thought it was about time I mentioned the end of the Blu-ray and HD DVD format war. Hmmm, those are currently the first and last items in the table.