Analog technology dominated the audio industry for more than a century. Beginning with the first primitive analog devices of the 1870s, they were often the sole viable means of recording sound until the introduction of the compact disc in the 1980s. Although some forms of audio are now approaching obsolescence, one form continues to cling to life due to its unique virtues. It was also the principal medium for early computer data storage, with even some computer designs being not digital, but entirely analog.
Identification
Analog refers to a process for recording information by copying them as a continual wave in or on the media. This is a different and older method of recording data from digital means, which operates by converting data into numbers. Analog was the means by which audio was recorded for decades.
Types
There are two major forms of audio analog media: magnetic tape and the gramophone record. Although CD and MP3 technology has largely superseded these analog technologies, neither has become entirely obsolete and disappeared from regular use. Magnetic tape was also used as a medium for data storage in early computers, and some computers like the Polish AKAT-1 were non-digital, all-analog devices.
Function
The gramophone record (often simply "record") is usually made from vinyl. The method used for putting audio information on a record is called groove recording, first developed for practical use by Thomas Edison in 1877. Disc records using this technology were first invented in 1888, but records as they are commonly thought of did not enter circulation until the early 20th Century.
Magnetic tape recording works by imprinting a magnetic signal onto the tape, and then reading them back while the tape is played at a constant speed. The format has taken many forms, from reel to reel to 8 track to cassette tape. The earliest practical examples used a wire and date to 1929.
An analog computer was a curious early experiment in computing technology. Like a digital computer, they used electricity. However, instead of using electric pulses as digital code, the analog computer used them in substitution for the mechanics that had previously been used in mechanical and hydraulic computer designs (such as were used in World War 2 era gun sights).
Benefits
The main benefit of the magnetic tape recording was that it could be used over and over again. With the rise of digital media, magnetic tape is nearing obsolescence, but it is slow to leave general use because the technology is well-understood and easy to operate.
Gramophone records continue to be favored by DJs and aficionados. The sound reproduction quality of a record is actually quite superior to that of a CD, but the record also requires far greater care (scratching, cleaning).
Analog computers offered few real advantages over digital computers, and were soon rendered an obsolete, dead end technology in most applications.
Considerations
The one great problem with both forms of analog audio was degradation. Even with perfect care, a record degrades slightly with each playing. This is because it is a physical object, and playing it wears it down. Magnetic tape was never as good at recording sounds as digital media, and is also prone to degradation.
Tags: analog computer, computer designs, data storage, digital media, forms audio, gramophone record
