by
Kyran de Keijzer
-
July 7, 2017

The recording industry, as many other industries, has fallen to the mercy of the never ending technical innovation and progression. Over and over again has the industry tried to contain and control this progress, but with no success. Every major shift in the last 100 years regarding audio recording formats have resulted in a decline in sales and vast disruption. In this article, we’re going to cover the history of recording formats, recording techniques and how technical innovation has and always will, change the way we record and listen to music.

ACOUSTICAL RECORDING

Recording

The earliest method of sound recording and reproduction involved the live recording of a performance directly to a recording medium by an entirely mechanical process, often called “acoustical recording”. In the standard procedure used until the mid-1920s, the sounds generated by the performance vibrated a diaphragm with a recording stylus connected to it while the stylus cut a groove into a soft recording medium rotating beneath it. To make this process as efficient as possible, the diaphragm was located at the apex of a hollow cone that served to collect and focus the acoustical energy, with the performers crowded around the other end. Recording balance was achieved empirically. A performer who recorded too strongly or not strongly enough would be moved away from or nearer to the mouth of the cone.

These early recordings were of low fidelity and volume and captured only a narrow segment of the audible sound spectrum (from around 250 Hz up to about 2,500 Hz), so musicians and engineers were forced to adapt to these sonic limitations. Bands and performers of that period often favored louder instruments such as trumpet, cornet, and lower-register brass instruments (such as the tuba). Performers had to also arrange themselves strategically around the horn to balance the sound, and to play as loudly as possible. The playback system at the time, the phonograph, was similarly limited in both frequency range and volume. By the end of the acoustic era, the moving recording disc, which we know now as a vinyl record, had become the standard medium for sound recording, and its dominance in the domestic audio market lasted until the end of the 20th century.

Phonograph / Gramophone

The phonograph was invented by Thomas Edison in 1877. It could both record sound and play it back making it the first recording device in the world. The earliest type of the phonograph recorded on a thin sheet of tinfoil wrapped around a grooved metal cylinder. A stylus connected to a sound-vibrated diaphragm indented the foil into the groove as the cylinder rotated. The stylus vibration was at an angle so that the depth of the indentation varied with the audio-frequency changes in air pressure. The sound could be played back by tracing the stylus along the recorded groove and acoustically coupling its resulting vibrations to the surrounding air through the diaphragm and a so-called “amplifying” horn.

The crude tinfoil phonograph proved to be of little use. It was not until the late 1880s that an improved and much more useful form of phonograph was marketed. These new machines recorded on easily removable hollow wax cylinders and the groove was engraved into the surface rather than indented. However, after the commercial success of this new machine, one seemingly negligible disadvantage became a major problem: the difficulty of making copies of a recording in large quantities.

At first, recordings were copied by acoustically connecting a playback machine to one or more recording machines through flexible tubing, an arrangement that degraded the audio quality of the copies. Later, a pantograph mechanism was used, but it could only produce about 25 fair copies before the original was too worn down. During a recording session, as many as a dozen machines could be arrayed in front of the performers to record multiple originals. Still, a single “take” would ultimately yield only a few hundred copies at best, so performers were booked for marathon recording sessions in which they had to repeat their most popular numbers over and over again. By 1902, successful molding processes for manufacturing prerecorded records had been developed.

ELECTRICAL RECORDING

Recording

Until the mid-1920s records were played on purely mechanical record players usually powered by a wind-up spring motor. The sound was amplified by an external or internal horn that was coupled to the diaphragm and stylus. The recording process was, in essence, the same non-electronic setup operating in reverse, but with a recording, stylus engraving a groove into a soft wax master disc and carried slowly inward across it by a feed mechanism.

The arrival of electrical recording in 1925 made it possible to use sensitive microphones to capture the sound and greatly improved the audio quality of records. These microphones had a much wider range of frequencies that could be recorded, the balance of high and low frequencies could be controlled, and the signal could be amplified to such a level that was accurate recording. The leading record labels switched to the electrical process in 1925 and the rest soon followed.

Electrical recording increased the flexibility of the process dramatically, but the performance would still be cut directly to the disc, so if a mistake was made the whole recording was spoiled. Disc-to-disc editing was possible, by using multiple turntables to play parts of different “takes” and recording them to a new master disc, but it was extremely difficult to do this with much accuracy. It was rarely done, except for in editing some early sound films and radio recordings.

Secondly, it made it more feasible to record one part to disc and then play that back while playing another part, recording both parts to a second disc. This, what we know now as overdubbing, enabled studios to create recorded “performances” that feature one or more artists each singing multiple parts or playing, multiple instrument parts, which would not have been possible in a live recording. The first commercially issued records using overdubbing were released by the Victor Talking Machine Company in the late 1920s. However overdubbing was of limited use until the advent of audio tape.

MAGNETIC RECORDING

Recording

The first magnetic recording technique was called magnetic wire recording. During this process, a recording is made of thin steel or stainless steel wire. The wire is pulled rapidly across a recording head, which magnetizes each point along the wire in accordance with the intensity and polarity of the electrical audio signal being supplied to the recording head at that instant. Later the wire is drawn across the same or a similar head while not being supplied with an electrical signal. The variance in the magnetic field recreates the original signal at a reduced level.

Magnetic wire recording was replaced by magnetic tape recording, but, the principles and electronics involved were nearly identical. Wire recording initially had the advantage that the recording medium itself had already been fully developed, while tape recording was held back by the need to improve the materials and methods used to manufacture the tape.

Fun fact: on Christmas Day, 1932 the British Broadcasting Corporation first used a steel tape recorder for their broadcasts. The device used was a Marconi-Stille recorder, a huge and dangerous machine which used steel tape that had sharp edges. The tape was 0.1 inches wide and 0.003 inches thick running at 5 feet per second past the recording and reproducing heads. This meant that the length of tape required for a half-hour program was nearly 1.8 miles and a full reel weighed 55 pounds.

Magnetic Tape

The real shift from acoustic recording to magnetic recording was through the introduction of magnetic tape. The world’s first practical magnetic tape recorder, the ‘K1’, was created in 1935. During World War II, an engineer at the Reichs-Rundfunk-Gesellschaft discovered the “AC biasing technique”. With this technique, an inaudible high-frequency signal, typically in the range of 50 to 150 kHz, is added to the audio signal before being applied to the recording head. This technique radically improved the sound quality of magnetic tape recordings. By 1943 this technique had developed into stereo tape recorders.

American audio engineer John T. Mullin and entertainer Bing Crosby were key players in the commercial development of magnetic tape. Mullin was given two suitcase-sized AEG ‘Magnetophon’ high-fidelity recorders and fifty reels of recording tape. He had them shipped home and over the next two years, he worked on the machines constantly, modifying them and improving their performance. His major aim was to interest Hollywood studios in using magnetic tape for movie soundtrack recording.

Mullin gave two public demonstrations of his machines, and they caused a sensation among American audio professionals—many listeners could not believe that what they were hearing was not a live performance. By luck, Mullin’s second demonstration was held at MGM studios in Hollywood and in the audience that day was Bing Crosby’s technical director, Murdo Mackenzie. He arranged for Mullin to meet Crosby and in June 1947 he gave Crosby a private demonstration of his magnetic tape recorders.

Crosby was stunned by the amazing sound quality and instantly saw the huge commercial potential of the new machines. Live music was the standard for American radio at the time and the major radio networks did not permit the use of disc recording in many programs because of their comparatively poor sound quality. But Crosby disliked the regimentation of live broadcasts, preferring the relaxed atmosphere of the recording studio.

Mullin’s tape recorder came along at precisely the right moment. Crosby realized that the new technology would enable him to pre-record his radio show with a sound quality that equaled live broadcasts and that these tapes could be replayed many times with no appreciable loss of quality. Mullin was asked to tape one show as a test and was immediately hired as Crosby’s chief engineer to pre-record the rest of the series.

Crosby became the first major American music star to use tape to pre-record radio broadcasts and the first to master commercial recordings on tape. The taped Crosby radio shows were painstakingly edited through tape-splicing to give them a pace and flow that was wholly unprecedented in radio. Mullin even claims to have been the first to use “canned laughter”; at the insistence of Crosby’s head writer, Bill Morrow, he inserted a segment of raucous laughter from an earlier show into a joke in a later show that had not worked well.

Keen to make use of the new recorders as soon as possible, Crosby invested $50,000 of his own money into Ampex, and the tiny six-man concern soon became the world leader in the development of tape recording, revolutionizing radio and recording with its famous Ampex Model 200 tape deck.

MULTITRACK RECORDING

NRG Recorders

The next major development in the magnetic tape era was multitrack recording. This process divides the tape up into multiple tracks parallel with each other and in perfect synchronization. This development was quickly followed with 2-track recording (stereo sound), which divided the recording head into two tracks. 2-Track recording was rapidly adopted for modern music in the 1950s because it enabled signals from two or more separate microphones to be recorded simultaneously, enabling stereophonic recordings to be made and edited conveniently. Stereo quickly became the norm for commercial classical recordings and radio broadcasts, although many pop music and jazz recordings continued to be issued in mono until the mid-1960s.

Much of the credit for the development of multitrack recording goes to guitarist, composer and technician Les Paul, who also helped design the famous electric guitar that bears his name. His experiments with tapes and recorders in the early 1950s led him to order the first custom-built eight-track recorder from Ampex, and his pioneering recordings with his then wife, singer Mary Ford, were the first to make use of the technique of multitracking to record separate elements at different times. Paul’s technique enabled him to listen to the tracks he had already taped and record new parts in time alongside them.

Multitrack recording was immediately taken up in a limited way by Ampex, who soon produced a commercial 3-track recorder. These proved extremely useful for popular music since they enabled backing music to be recorded on two tracks (either to allow the overdubbing of separate parts or to create a full stereo backing track) while the third track was reserved for the lead vocalist. Three-track recorders remained in widespread commercial use until the mid-1960s and many famous pop recordings — including many of Phil Spector’s so-called “Wall of Sound” productions and early Motown hits — were taped on Ampex 3-track recorders. Engineer Tom Dowd was among the first to use the multitrack recording for popular music production while working for Atlantic Records during the 1950s.

4-Track Recording

The next important development was 4-track recording. The advent of this improved system gave recording engineers and musicians vastly greater flexibility for recording and overdubbing, and 4-track was the studio standard for most of the later 1960s. Many of the most famous recordings by The Beatles and The Rolling Stones were recorded on 4-track, and the engineers at London’s Abbey Road Studios became particularly familiar with a technique called “reduction mixes” in the UK and “bouncing down” in the United States, in which several tracks were recorded onto one 4-track machine and then mixed together and transferred (bounced down) to one track of a second 4-track machine. In this way, it was possible to record literally dozens of separate tracks and combine them into finished recordings of great complexity.

All of the Beatles classic mid-1960s recordings, including the albums Revolver and Sgt. Pepper’s Lonely Hearts Club Band, were recorded in this way. There were limitations, however, because of the build-up of noise during the bouncing process. Abbey Road engineers are still famed for their ability to create dense multitrack recordings while keeping background noise to a minimum.

4-Track recording also enabled the development of quadraphonic sound, in which each of the four tracks was used to simulate a complete 360-degree surround sound. A number of albums were released both in stereo and quadrophonic format in the 1970s, but ‘quad’ failed to gain widespread commercial acceptance. It was the direct precursor of the surround sound technology that has become standard in many modern home theater systems. In a professional setting today, such as a studio, audio engineers may use 24 tracks or more for their recordings, using one or more tracks for each instrument played.

DIGITAL RECORDING

Recording

The first digital consumer audio format was the Digital Audio Tape (DAT). This format used rotating heads on a narrow tape contained in a cassette. DAT records at sampling rates of 48 kHz or 44.1 kHz, the latter being the same rate used on compact discs. The bit depth was 16 bits, which was also the same as compact discs. DAT was a failure in the consumer-audio field (too expensive, too finicky, and crippled by anti-copying regulations), but it became popular in studios and radio stations.

Within a few years after the introduction of digital recording, multitrack recorders (using stationary heads) were being produced for use in professional studios. In the early 1990s, relatively low-priced multitrack digital recorders were introduced for use in home studios. The most notable of this type of recorder is the ADAT. Developed by Alesis and first released in 1991, the ADAT machine is capable of recording 8 tracks of digital audio onto a single S-VHS video cassette. The ADAT machine is still a very common fixture in professional and home studios around the world.

In the consumer market, tapes and gramophones were largely displaced by the CD. These recording media are fully digital and require complex electronics to playback. Digital sound files can be stored on any computer storage medium. The development of the MP3 audio file format, and legal issues involved in copying such files, has driven most of the innovation in music distribution since their introduction in the late 1990s.

As hard disk capacities and computer CPU speeds increased at the end of the 1990s, hard disk recording became more popular. As of early 2005, hard disk recording takes two forms. One is the use of a standard desktop or laptop computers, with adapters for encoding audio into two or many tracks of digital audio. These adapters can either be in-the-box soundcards or external devices, either connecting to an in-box interface cards or connecting to the computer via USB or Firewire cables. The other common form of hard disk recording uses a dedicated recorder which contains Analog-to-digital and digital-to-analog converters as well as one or two removable hard drives for data storage. Such recorders, packing 24 tracks in a few units of rack space, are actually single-purpose computers, which can, in turn, be connected to standard computers for editing.

CONCLUSION

There have been massive shifts in recording techniques and mediums over the last century, all of which have drastically shifted the recording industry. It begs the question, “what happens next?”. As technological innovation proceeds to happen at an exponential rate, it’s difficult to foresee the changes that are to come. What we can do is adapt to any situation the best we can, which is one of the main reasons why we at NRG Recording Studios have been able to continuously succeed as an independent recording studio. We adapt to any change faster than our competition.

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