An excerpt from chapter 8 my book, Music: Notation and Practice in Past and Present, available for course adoption in Spring 2012 from National Social Science Press.
The acoustic phenomena discussed in Chapter 7 would exist with or without human (or other) intelligence and culture. Music, however, would not. In fact, music may itself be an indicator of intelligence, and has been interpreted as such by some of those who study whale-song or bird calls. Tellingly, when American space scientists wished to include a message to other intelligent beings on the Voyager space probes, in addition to an engraved “license plate” depicting humans and our location in space, they used precious space and weight on the probes to include recorded music from around the world.
How then, do acoustical laws meet the mysteries of consciousness and intelligence to allow musical creativity to be made manifest? The answer is through a musical instrument, which in its broadest definition is an interface between a mind with its musical ideas and the broader physical world. Almost any object can be used in such a way, of course. One need only think of an eight-month old baby slapping the tray of his high chair in a steady pulse, whether to communicate his desire to be fed or for the sheer joy of the resonant thump that results. At the same time, he may be vocalizing, and within a year will likely be clanging together pots and pans in the kitchen. Humans are innately musical beings, and we will always find ways to express our fascination with controlled sound.
Many musical instruments are found sounds, that is, an object—a body part, a part of the natural world, or a human-created artifact—is pressed into service as a music-making device. An example would be the use of the washboard as a percussion instrument in American styles such as zydeco, the folk music of the bayou country of Louisiana. On the other hand, just as in every other human culture, there is a tendency to create artifacts with the intention of using them in music making. Frequently, these artifacts are copied and refined over periods of decades and centuries, sometimes achieving a relatively fixed, specialized form. What follows is a survey of the musical artifacts of Western culture, which includes representatives of every major type of instrument.
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Readers born before the year 2000 had the distinction of living in a unique century in the musical history of our species, namely, the era in which an entirely new means of making music was invented, developed and brought to mass consciousness. This new category of instrument is termed the electrophone, and is an instrument in which the primary source of the sound is the conversion of electrical energy to acoustic energy.
Some ethnomusicologists include instruments that merely rely on amplification of a traditional sound source in the category of electrophones. For example, an electric guitar is a version of a fretted string instrument (a chordophone) in which the motion of the metal strings agitates a magnetic field, creating an electric current that is transmitted to an amplifier. The strings themselves do produce a certain amount of sound, although the characteristic sound of the instrument is dependent on the amplification and processing of the electric signal, which is then converted to sound. Similar electric instruments include the electric piano and electric violin. By this definition, the electrophones might even include a vocalist singing into a microphone. Other ethnomusicologists recognize a narrower definition for electrophones, namely, instruments in which the sound is wholly generated by electrical energy rather than by electronic modification of an acoustical source.
The first electrophones fit this narrower definition, and were conceived and created at the beginning of the electric era, with the first electronic instrument generally understood to be Thaddeus Cahill’s Telharmonium of 1897, which was an early form of electronic organ, in which spinning tone wheels created an oscillating electrical field that was then transformed to sound using telephone receivers. Later versions of the Telharmonium were capable of basic additive synthesis, in which signals from two or more oscillators were combined to create more complex sounds. Because of its massive size—later versions weighted up to 200 tons—the Telharmonium was impractical for all but demonstration purposes.
Many of the basic concepts of the Telharmonium—its organ-like keyboard interface, its use of additive synthesis and oscillators—were incorporated into later electronic instruments, and the most ubiquitous electronic instruments have been similar organ-like devices, often referred to as synthesizers. Because of the rapid changes in electronic and computer technology through the 20th century, no single synthesizer has become a standard instrument in the same way that, say, the guitar has become a standard fretter string instrument in Western music. Some models of synthesizer, however, have become iconic for their appearance in widely-known music. In the concert hall, French composers of the 1940s and 1950s made effective use of the ondes martenot, a keyboard instrument whose portamento effects can be heard in Olivier Messiaen’s Turangalila-Symphonie, among other works. The most important and iconic sounds, however, were those produced by the Moog synthesizer, and its smaller successor the Minimoog. Produced by Dr. Robert Moog and the company that bears his name, these instruments were among the first commercially available synthesizers that could be operated by a musician rather than a technician. Beginning with the iconic 1968 classical album Switched-On Bach by Wendy (nee Walter) Carlos and continuing with the use of the Minimoog by rock musicians of the 1970s such as Kraftwerk, Yes and Tangerine Dream, the sounds of Moog instruments became for most listeners the sound of electronic music.
One of the most interesting early electronic instruments was the theremin, named after its inventor Leon Theremin, patented the instrument in 1928. Unlike almost every other instrument, the performer does not have to make physical contact with the theremin. Instead, the magnetic field of the performer’s hands disrupts the magnetic fields generated by two rods that protrude from the box containing the electronics of the instrument. One hand affects pitch and the other affects dynamics. The sound of the theremin is most familiar to modern ears from the Beach Boys’ 1966 song Good Vibrations, although the precise instrument used was a similar instrument known as a tannerin. Film composers of the 1950s and 1960s often used the eerie, wobbly sound of the theremin to great effect in science-fiction and suspense-themed scores, including well-known uses of the instrument in Bernard Herrmann’s music for The Day the Earth Stood Still and Miklos Rosza’s score for Spellbound.
The Moog instruments and similar instruments up to the 1970s can be termed analog synthesizers because they generate tone directly from electrical oscillators. With the development of microprocessor technology in the 1970s, a shift to digital synthesizers, led by the Yamaha Corporation, began to place electronic music into the hands of the mass market to an even greater extent by the 1980s. Rather than incorporating a bank of oscillators, a digital synthesizer stores the waveforms of sounds in computer memory in the form of tables of numbers known as wave tables. A command to the processor to play a note—perhaps by the pressing of a key on a piano-style keyboard—results in the wave table for that note being played back, either in a continuous loop, or with appropriate attack and decay envelopes. The major development in the 1980s was the sampler, which permitted a user to load their own wave tables with sounds from the outside world—either instrumental or vocal noises, sounds taken from recordings or from natural or manmade noises. Sampling techniques, including the drum machine, a device for creating short loops of samples, usually taken from percussion instruments, had a revolutionary effect on popular music in the last two decades of the 20th century.
Finally, the availability of ever-cheaper, ever-faster computing power, led to developments that allow not just the production of digital sound but its recording in real-time from multiple sources on home computers. The first years of the 21st-century saw the development of software synthesizers, in which the characteristics of an analog or digital synthesizer are mimicked by a software application, perhaps as a plug-in in a larger sequencing program. Most importantly, recording and sound synthesis technology that, in the 1960s, would have required the resources of a large corporation or other institution, was effectively placed into the hands of millions of amateur and professional musicians with the resulting revolution in the production and distribution of music having impacts which are still being felt, not the least of which has been the dismantling of the recording industry as it existed as late as the year 2000.