A synthesizer is an electronic musical instrument that produces sounds by generating and combining signals of different frequencies. Digital synthesis involves the use of a frequency synthesiser processor component which calculates mathematical functions, the results of which are signals of different frequencies.
The following is a very short overview of the basic categories in which synthesizers fall:
Modular Synthesizers
In the early days, each component of a synthesizer was self contained in its own individual box – a module. Hence the term “modular”.
Analog Synthesizers
These synthesizers use analog based circuitry, such as oscillators and filters, that are controlled by voltage.
Digital Synthesizers
These are synthesizers that use digital methods to generate sound. Typically they start out with a sound source and then process it through various digital algorithms.
Software Synthesizers
These digital synthesizers model ‘organic’ musical instruments with software instead of using hardware methods.
Instead of creating real acoustic sounds, synthesizers produce electrical signals which are then amplified through a loudspeaker or headphones. You use a synthesizer in much the same way that you would play a piano; via a keyboard. A synthesizer mimics the hammer striking a string in a piano by turning on and off electronic circuits.
Although the first synthesizer was built at RCA, USA in 1955, people had already started experimenting with producing music electronically as early as the 1870’s. The first electronic instrument was invented by Leon Theremin in 1920 and was called the aetherphone (later renamed the theremin). The theremin has been used in places like the soundtrack to “Forbidden Planet” and the Beach Boys’ song “Good Vibrations”.
The first synthesizers were very expensive and hard to play. We had to wait until the 1960s before synthesizers became much more user friendly. Pioneers on the synthesizer scene of that era include Don Buchla and Bob Moog (of legendary MiniMoog fame). By the 1970’s, synthesizer production was on a much larger scale.