Synthesizer

Synthesizer as used in music, is a term derived from a Greek word syntithetai < synthesis (συντίθεται < σύνθεσις) and is used to describe a device capable of generating and/or manipulating electronic signals for use in music creation, recording and performance. A synthesizer is capable of generating and manipulating electrical signals which are equivalent to audio tones such as musical notes. Synthesizers can create electrical signals which appear as sound when they are used to drive audio amplifiers. These tones are generated by electrical circuits which may work by manipulating a signal through a series of oscillators and filters in a analog circuit (as in analog synthesizers), or may perform mathematical manipulation of signal using a microprocessor and digital signal processing (as in digital synthesizers), or by a combination of both methods. Synthesized sounds may sound dramatically different than recordings of natural sounds , though sampling synthesizers significantly blur this distinction.

Music synthesizers sometimes include a keyboard, which makes them reminiscent of certain traditional musical instruments, like a piano or an organ. Various alternative or additional pitch controllers, such as "fingerboards" and "ribbons", have been employed as well. (See sound module.) Alternately, they may be controlled via a series of signals over a digital bus such as MIDI.

The term "speech synthesizer" is also used in electronic speech processing, often in connection with vocoders.