Synthesizer

A synthesizer is an electronic keyboard instrument capable of imitating the sound of many traditional instruments, and of producing unique musical sounds of its own.

The concept has a long history. The traditional pipe organ has numerous sets of pipes controlled with stops, producing a variety of different tone colors. Some have names like "flute," "strings," "trombone," and even "Vox humana" (human voice).

The word "synthesizer" derives from the concept of synthesizing a complex waveform out of simple ones, particularly sine waves. Fourier analysis consists of breaking a complex waveform into sine waves, so the converse process is called synthesis. The 1934 Hammond Organ used this technique, producing sine waves with stable and precise tuning by an electromagnetic system known as tonewheels. However, even though it was using additive synthesis, it was not called a synthesizer.

The first machine to use this word was the 1955 RCA Music Synthesizer, a room-sized machine using vacuum tubes. It was controlled by a prepunched paper tape, like a player piano. It was not a performance instrument, and the music prepared for it was played in strict rhythm. RCA release a few recordings produced by this device, but it was never more than a curiosity. Nevertheless, it was able not only to produce different timbres and tone colorations, but vibrato, and instrument-like attacks and decays. It really does sound rather like a modern "synthesizer."

By the late 1960s and 1970s, solid-state electronics made analog synthesizers more inexpensive and practical, and Robert Moog in particular developed a series of synthesizers which had keyboards as interfaces and began to attract the attention of musicians. A breakthrough occurred in 1968 when Walter Carlos released Switched-on Bach, an LP of Bach piece which he "realized" on a specially-built Moog synthesizer. These synthesizers were still not performance instruments; they could only play one part at a time, and Carlos had to assemble his pieces on a multitrack recorder. The genuinely musical quality of his "realizations" took the synthesizer out of the realm of a novelty or a source of sound effects (like the Theremin) and touched off a wave of synthesizer use.

Notes and references

• The 1955 RCA Music Synthesizer. Has links to recorded examples.