Sound Recording – Then and Now

Sound Recording

By Dave Austin, “Music Professor”

As DJs and others associated with the music industry, we take for granted the clear concise sound reproduction we enjoy today.  However, like all technologies, there’s been a long and involved process of trial, error and refinement to reach the current state.  In this article, I’d like to share some of this history in the hope that it will provide a better understanding and appreciation, and encourage you to delve deeper into the subject.

Thought to be the earliest method of recording sound was a mechanical process of recording live sound onto a recording medium.  The sound was captured by means of a diaphragm with a needle attached to it.  Performers would gather around a large cone in which the diaphragm was located, as the needle cut a spiral groove into a recording medium.

It was1857 when the first device which could capture sound waves as they passed through the air was developed.  The phonautograph was not intended as a playback device, but rather a method for studying a visual pattern of the sound.  It employed a piece of soot-coated paper around a rotating cylinder.  A stylus traced lines into the soot-coated paper.

In 1877, it was found that the process could be reversed and sound could be produced by photoengraving the lines into a metal medium.  These early recording were “rediscovered” in 2008 and were converted to digital audio files.

It was also in 1877 that Thomas Edison created a device with a cylinder coated with wax, foil, metal which could be etched by a stylus – and played back and amplified.  This led to the gramaphone which was patented in 1887, using a flat disc of shellac rather than a wax cylinder.  As these discs were cheaper and easier to produce, and became the standard medium.  Also, 78 RPM was the standard speed at which these early discs rotated, but as sound technology improved, the 45, 33 1/3 and 16 RPM speeds followed.

Fast forward to 1925 and electrical recording was developed, greatly improving the quality of both the discs and they sound they contained.  Between 1925-1930, sound reproduction was a combination of electrically recorded discs and acoustic phonographs.  Electrically powered phonographs were introduced in 1930, but the magnetic cartridge and electronic reproduction did not become common until late in the decade. The development of electrical recording also made it possible to use microphones to capture sound.

It was at this time that a common modern process called overdubbing was developed.  One segment of a performance was recorded to a disc, then that disc was played back while a second segment was performed.  Both the disc playback and the new (usually live) performance were simultaneously recorded to another disc.  The fist of these over-dubbed recordings were released by Victor Talking Machine Company in the late 1920s.

It is at this point I need to talk about magnetic recording – first wire recording, and later, magnetic tape – which came into general use in the 1940s.  However, the principle of magnetic recording was first proposed as early as 1898.  Wire recorded, which were mostly used for dictation and voice recording, were not very user friendly as the wire easily became tangled or knotted.  Also, the acoustic quality of those recordings was poor.

I found it interesting that the first broadcast utilizing a wire recorder was made on Christmas Day, 1932 by the British Broadcasting Corporation.  It was a huge and dangerous machine using three millimeter razor tape and running at about 300 feet per minute over the reproduction heads.  A one-half hour program required almost two miles (10,032 feet) of tape weighing 55 pounds!

On a more practical note, the first magnetic tape recorder came about in 1938, developed by engineers at AEG.  By 1943, these engineers came up with stereo tape recorders.

During WW II, the Allies noticed that transcribed radio broadcasts seemed to have the same audio quality as live, and were much longer than 78 RPM discs would have allowed.  At the end of the war, a number of Magnetophon recorders which included all of the features of analogue magnetic recording were found at Radio Luxembourg.

An American audio engineer, Jack Mullen, and singer Bing Crosby were key players in the development of magnetic audio tape.  At the end of the war, Mullen shipped two Magnetophon recorders and a number of reels of tape back to the United States, were he worked for two years to modify the machines’ performance.  He intended to market them to Hollywood movie studios to record soundtracks.  When he demonstrated the machines, they caused a sensation among audio professionals.  In one of those demonstrations, Bing Crosby’s technical director was in the audience and arranged for Mullen to give Crosby a personal demonstration.

To make a long story short: Crosby liked what he heard.  During this period, radio networks did not permit the use of recorded music because of the poor sound quality.  Crosby disliked live broadcasts and asked NBC to allow him to record his 1944-45 series of programs.  The networks refused and Crosby sat out the season in protest.  Mullen was hired as Crosby’s sound engineer to pre-record the singer’s programs, making Crosby the first major American star to utilize pre-recorded radio programs.  As an aside, Crosby invested $50,000 in a small company known as Ampex and the little six-man company soon became the world’s leader in tape recording.

The next leap forward came with multitrack recording in which a recording tape is divided into multiple tracks, all running parallel with one another in perfect synch.  First developed by German engineers in 1943, two track (stereo) became the norm for recorded music.  Still, the older single track or monophonic sound lasted well in the 1960s.

We could not mention multitrack recording without guitarist Les Paul.  He and his then-wife, Mary Ford, were the first to make use of this multitracking technique with a custom-built Ampex eight track recorder.

Most users employed a three-track machine for recording commercial music, and these machines were used until the mid 1960s.  Phil Spector’s famous “Wall of Sound” and many Motown hits were produced on three-track machines.

Next, four-track gave engineers and musicians still greater flexibility for recording and overdubbing.  Many of the Beatles and Rolling Stones’ hits were four-track recordings.  From these four-track machines, there came quadraphonic recording.  However, this early “surround sound” failed to catch on, but is the father of our modern surround sound, popular in movie and home theatre systems.

In 1963, Phillips introduced the compact cassette tape, a small convenient format that dominated the market for a decade, despite its somewhat inferior audio quality.  Lest someone accuse me of leaving it out, let’s mention the relatively short-lived 8-track tape of the period which was used primarily in automobiles.

By nature, tape recordings have an inherent hiss, caused by particles on the tape moving over the heads of the playback unit.  To combat this, Dolby Laboratories developed a system to negate this unwanted hiss and dramatically improved the sound quality of tape recording.

By the 1980s, digital recording was in, and tape was being phased out, although it has not totally gone away.  Many professional studios still use analogue recorders for multitracking and mixdown.)  We also had digital audio tape (DAT), another interim technology which failed to establish a viable market although it is still used in professional applications.

Compact discs are now giving way to digital recording which allows sound files to be stored on any computer storage medium.

So, what’s next?  Your guess, or mine, would probably be as good as the next person’s.   It appears that digital is here to stay, but analogue refuses to die.  CDs are going the way of the tape cassette while vinyl recordings are making an amazing comeback.

As for me, I’m anxious to see what over the technology horizon.

 

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