Final Project: Audio Production History

I was originally planning on doing a more in-depth mixing project, but, being pressed for time, I'm not able to finish that project, so instead please enjoy this summary of the history of audio recording and production!

In this early period in the history of audio production, clunky machines had to be used to capture and play back audio. Audio editing was not very feasible during this time period, even for professional musicians. Needless to say, the quality of early recording mediums was not that great: everything was mono, and everything lacked dynamic range.

Edouard Leon Scott invented the phonautograph in 1857. The phonautograph was the first sound recording device in history, although it wasn't very popular because of its unintuitiveness. It used paper or glass as a recording medium, and it worked by drawing the shape of sound waves onto that surface. This also meant that audio could not be played back, only recorded, so the machine had a very limited use case. It was only in 2008 when researchers, with the help of digital aid, were finally able to transcribe the "squiggles on a paper" created by a phonautograph and convert it into a real musical recording! The machine worked!

Alexander Graham Bell gained fame in 1876 with his invention of the telephone (which was really his improvement upon many people's work). The telephone allowed for the human voice to be transmitted via microphone over wire at lower levels of voltage, and, with subsequent innovations in repeaters, over great distances.

Thomas Edison invented the phonograph, the world's first practical audio recording and playback device, in 1877. The phonograph took an audio input to etch grooves into a tinfoil-covered spinning "phonograph cylinder". The lines could then be travelled over by a playhead, creating vibrations that could be amplified into real recorded music for the first time ever.

Invented independently by Thomas Edison and Emile Berliner, the carbon microphone was the first practical and popular microphone. It consisted of two metal plates separated by small pieces of carbon. When someone spoke, the first metal plate would act like a diaphragm and vibrate, creating an electrical signal that could pass down a wire and through, for example, a telephone. Carbon microphones were still used in telephones throughout the 20th century and can still be found in basic telephones today.

Emile Berliner invented the gramophone, which functioned the same was as Edison's phonograph except that it used discs as a recording medium rather than cylinders. Discs, or 'records', as they came to be known, would remain the most popular format for recording and replaying audio for another 100 years, until cassette tapes and CDs took the title in the 1980s.

Vlademar Poulsen invented the telegraphone in 1898. It used magnetic steel wire as a recording medium:

"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. By later drawing the wire across the same or a similar head while the head is not being supplied with an electrical signal, the varying magnetic field presented by the passing wire induces a similarly varying electric current in the head, recreating the original signal at a reduced level."

The recording was not of very high quality and it did not become as popular a method of recording as disks were to become, but it was useful in dictation and recording where low-fidelity was acceptable.

The Victor Talking Machine Company, founded by engineers experienced with Emile Berliner's gramophone, become popular in the 1900s for selling music on disc format and machines that could play those discs back.

In this period, recording technology evolved from being acoustic towards being electronic and magnetic. With the increasing popularity of disc records, as well as formats towards the end of this period, most middle-class Americans now had the ability to listen to music from the comfort of their home. Prerecorded music had become mainstream.

In 1925, the first electrically-amplified microphone, developed by Bell Laboratories and Western Electric, was used to capture sound onto disc records, producing a significantly better-sounding record when coupled with the right record player. Realizing this technology as the breakthrough to compete with radio, the two major record manufacturer companies, Victor and Columbia, immediately began producing and manufacturing electrical records. Victor called the improved-fidelity recording process "orthophonic" and developed a new line of record players called "Orthophonic Victrolas", scientifically designed to play these improved records.

The technology was kept secret from the public until it was revealed in a massive advertising campaign on "Victor Day", November 2, 1925. The Victrolas could reproduce frequencies between 60 and 6000 Hz, as opposed to the earlier acoustic records' dynamic range of between 250 and 2500 Hz. Electronic amplification enabled a multitude of new possibilities within the field of audio recording, and also allowed the process to become complicated enough for people to specialize as "audio engineers". The rotation rate of these electrical records was also finally standardized as 78 RPM in 1925.

Fritz Pfleumer pioneered the use of magnetic tape as a recording medium in 1928, which was built into the first practical magnetic tape machine in 1932. The technology was kept secret by Nazi Germany until the end of WWII, but allied observers suspected some invention when they heard obviously pre-recorded radio broadcasts that had the same quality as live broadcasts. When the technology was revealed to the rest of the world in 1945, it immediately became popular in recording studios because it was the highest quality recording possible, although it was impractical for direct consumer use because it was expensive, complicated, and bulky. Magnetic tape recording also allowed the development of hi-fi stereo recordings.

The long-played, or "LP" record was released by Columbia in 1948, and quickly became popular throughout the industry. Unlike 78RPM records, which could only hold one song on each side, LP records could hold entire albums. They were made from vinyl plastic, which is flexible and unbreakable in normal use. The records spun at 33 1⁄3 rpm and were produced in variants of 12- or 10-inch diameter. LP vinyl records remain a popular standard for analog music playback to the present day.

The famous guitarist, composer and technician Les Paul began to experiment with stereo multi-track recording in 1940. He continued to improve his concept designs, and in 1953 devised the idea of 8-track recording, where each track could be individually recorded, mixed, and amplified, before being combined onto one record. 8-track recording was commercially developed by the Ampex corporation, although the technology was so expensive that it was not popular outside of recording studios.

Tom Dowd was an influential recording engineer in the 1950s and 1960s. He replaced the multi-track 'mixing board' conceived by Les Paul with linear faders and the first common application of equalization, among other features. He redesigned the first modern recording studio with a control room and isolation for recording each track on a multi-track record separately. Recording on 8-track became standard with his influence at Atlantic Records.

Laurens Hammond developed spring reverb in his Hammond Organ in 1935. He did this because when people heard organs, they heard them in churches, where the sound could bounce off of the many surfaces and reverberate naturally. In small spaces and even carpeted spaces, this could not happen naturally, so spring reverb allowed sound to pass through a chamber with a spring that would create artificial reverb. Spring reverb units would later be used in recording studios in the 1940s and 1950s and became especially popular after the advent of multi-track recordings, where the reverb of individual instruments could be customized.

In 1957, the EMT-140 reverberation unit introduced a different type of artificial reverb for recording studios: plate reverb. Plate reverb essentially consisted of a vibrating metal plate:

"Despite its roughly 600 pound weight, the EMT 140 plate provided a smaller solution to large echo rooms. Additionally, a remote controlled damping pad system allowed the engineer to adjust the reverb time, offering substantially more control than possible with a traditional chamber. The sheet metal plate is suspended from its frame by springs, a transducer mounted at the center of the plate drives movement, and returns consist of pickups mounted on the plate. While the 140 was originally available only in mono, EMT released a stereo model in 1961."

Phillips developed the cassette tape in 1963. Their compact audio cassette, based on magnetic tape, was the first to combine the convenience of a tape recording format with the perk of not requiring manual threading. It was initially not popular, but a decade after its invention, cassettes began to dominate the consumer market alongside the vinyl record when their fidelity was improved. On stereo cassettes, the two channels were adjacent to each other, making them compatible with mono-players and vice versa. Cassette tape was 3.81mm wide (often given as 4mm or ⅛ inch), and moved at 4.76 cm/s (1⅞ ips). 

In this period, digital technology quickly became the most popular way to record and also play back music. Nowadays, we use digital audio workstations (DAWs) that can have dozens of effect plugins on hundreds of tracks. Many of these plugins are actually designed to emulate specific electronic techniques used during the preceding period. Also listed below are some landmarks that allowed digital audio to become popular, before it was.

Pulse-code modulation (PCM) is the foremost method used to digitally represent sampled analog audio signals. In a PCM stream, the amplitude of the analog signal is sampled regularly at uniform intervals, and each sample is quantized to the nearest value within a range of digital steps. For example, when converting analog audio to 16-bit digital audio (pictured) there are 16 steps for the analog signal to be quantized to; the number of steps is called the bit depth, and the higher the bit depth is, the more accurate it is to its analog counterpart. The 'sample rate' of digital audio is how many times per second (Hz) the amplitude is measured; higher sample rate, higher fidelity.

Analog has infinite detail, and when audio is converted from analog to digital, that infinite detail is condensed into a finite number of values, so when you digitize analog sounds, you naturally lose some information. The idea is to have a high enough bit depth and sample rate such that the detail lost is so minor you wouldn't be able to notice the difference. Early efforts to produce digital audio were not able to achieve this; as computers became more powerful, processing decent digital audio for real-time playback was possible. PCM was invented by British scientist Alec Reeves in 1937 and was used in other applications long before its first use in commercial broadcast and recording. It was only in 1967 that the first PCM-based audio recorder was developed by the NHK corporation in Japan.

Max Mathews wrote the first popular computer program designed to produce sounds. Despite its name "MUSIC", it couldn't really produce music, just simple sound waves; the computers at the time were also way too slow to synthesize music in real time, but they could use low-bit depth and low-sample rate PCM to output analog audio from designed digital signals. Mathews improved upon his algorithms and released MUSIC II through MUSIC V in the following years. All of these early programs faced limitations in dynamic range so they couldn't yet produce commercially viable sounds to compete with analog technology. Mathews continued to lead the development of digital music technology over the next decades.

Thomas Stockham was a Professor of Electrical Engineering at MIT, where he gained experience in creating digital audio tape recordings using a digital-to-analog converter (DAC) and a computer. Inspired by this technology, he left MIT in 1968 and founded a company, Soundstream, Inc. in 1975. He developed a 16-bit digital audio recorder using high-speed magnetic tape; the recorder had a sample rate of 50 kHz. Soundstream was the first commercial digital recording company in the United States and released its first commercial digital recording in 1978. Commercial digital audio recording was also simultaneously developed by the NHK and Nippon-Columbia companies in Japan. Digital audio recording only grew in popularity as all major record labels adopted it. In the present day, everything is recorded digitally.

The compact disc (CD) was developed by Philips and Sony and released in 1982. CDs quickly became the most popular consumer form of digital audio and essentially replaced analog vinyl records and cassette tapes. Unlike those formats, the quality of CD audio does not degrade over time because data is read with a laser. The CD uses a 44,100 Hz sampling frequency and 16-bit resolution, and can store up to 80 minutes of stereo audio, double what an LP disc can store.

In 2004 alone, 30 billion CDs were sold. By 2010, the annual total had dropped by more than half. Despite the revolutionary concept of digital distribution of audio on CDs, CDs were quickly superseded by digital audio files. In the 21st century, storage drives have become dense and cheap enough that people can store thousands of songs on their computer, without any need for an external physical storage medium. At the same time, internet access and internet speeds have reached the point where almost anyone in America has access to download or stream their choice of millions of songs and audio recordings. Digital audio files can be in lossless or lossy formats. Lossless audio formats, such as .wav and .aiff, use only simple PCM through to the DAC, but lossy audio files, such as .mp3, .m4a, and .opus, use algorithms to compress file size, allowing more songs to be stored with the same amount of disk space; the downside to lossy files is the requirement for increased processing power, although to modern computers this does not matter, and degraded quality, which also does not matter to most people's ears.

Soundstream designed a proprietary digital audio workstation in 1978, the first of its kind. In the late 1980s, some consumer computers had enough power to edit audio files. It was not until the 2000s, however, that computers became powerful enough to enable the proliferation of the modern digital audio workstation (DAW). Modern DAWs can have dozens of effect plugins on hundreds of tracks, allowing the easy recreation and synthesis of any sound you can hear; many of these plugins are actually designed to emulate specific electronic techniques used during the analog period. In 2017, the most popular DAWs include Pro Tools, Logic Pro X, Audacity, Ableton Live, and FL Studio. With the advent of consumer DAWs, everyone with access a computer built in the last ten years has the ability to produce music of equal or better quality to the best recording studios from a generation ago. Audio production itself has become mainstream.