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George Brock-Nannestad
Postal:
Patent Tactics Resedavej 40, DK-2820 Gentofte, Denmark
Email:
gbn@newmail.dk
Against All Odds: Commercial Sound Recording and Reproduction in Analog Times
Today sound recording is for everyone, but for the first 100 years, it was very mechanical and complex.
Introduction
We are surrounded by recorded sound wherever we go, and we have access to the largest selection ever of recorded sound via personal devices such as the iPod or from the Web. Development in sound recording has spanned more than 125 years, over which time we have seen continuous technical progress from extremely prim- itive beginnings (Hoffmann, 2005).
Today, audio technology is predominantly digital, which places it on a very solid footing in which storage is actually a computer file that is amenable to backup so that we shall never lose anything! But the earlier technologies comprising analog recording systems still account today for the majority of sound that has ever been recorded. There is, hence, a good reason to look back at early recordings (Nixon, 1945; Olson, 1954).
The time limit of the present overview is about 1960 because by then the analog medium of widest distribution, the mechanical record, was fully matured. It was then overtaken by the more democratic utility, the magnetic tape compact cassette, which, however, had a less inherent quality. Sound records have always been used both commercially and professionally.
Historical overviews risk being overburdened with detail, in particular when deal- ing with such a broad field as sound recording and reproduction, which draws on so many phenomena and involves mechanics, acoustics, electronics, and chem- istry. Development was explosive starting in 1887, and we need to concentrate on the surviving technologies. In the United Kingdom alone, about 4,000 patents were published on phonograph-related inventions until about 1960, but only a few hundred had any lasting impact. Some readers with specialized knowledge will undoubtedly find gaps in this presentation. However, a selection of the relevant literature is given in References to aid further exploration of the subject. A Ger- man (Bergtold, 1959) and a French (Gilotaux, 1971) reference are also included.
Sound recording technology starts with a transducer and ends with a transduc- er. The actual element that interacts with the sound pressure variations is a dia- phragm. The sound that we are interested in is picked up by a microphone dia- phragm, which converts the sound into an electrical signal that is a representation of the sound pressure variations. The electrical signal is taken to a storage device, and when we want to listen to the sound, the electrical signal is sent to an ampli- fier, which drives a loudspeaker or headphones. Apart from a means for storing the signal, a public address system has the same components (Beranek, 1954).
12 | Acoustics Today | Fall 2016 | volume 12, issue 3 ©2016 Acoustical Society of America. All rights reserved.