What is a synthesiser?

A selection of definitions from the web on what a synthesiser (synthesizer) is:

• An electronic instrument often played with a keyboard and producing complex sounds, such as those of various other instruments.
• An electronic musical instrument which produces audio signal either by the direct manipulation of an electrical signal (”analog”) or by using mathematical functions to alter a stream of numbers (”digital”).
• A musical instrument that can generate audio WAVEFORMS electronically and modulate them to create new audio waveforms.
• A musical instrument that generates sound electronically and is designed according to certain principles developed by Robert Moog and others in the 1960s. A synthesizer is distinguished from an electronic piano or electronic organ by the fact that its sounds can be programmed by the user, and from a sampler by the fact that the sampler allows the user to make digital recordings of external sound sources.
• Electronic instrument that produces a wide variety of sounds by combining sound generators and sound modifiers in one package with a unified control system.
• An electronic music device that allows the control of the pitch, timing and tone of one or more signals.
• An electronic apparatus with a keyboard capable of duplicating the sounds of many musical instruments, popular among Post-Modernist composers and musicians.
• An electronic device that can generate and modify sounds electronically as in “synthesizer programming” in music (as used by the group Emerson, Lake, and Palmer).
• A synthesizer (spelling var. synthesiser) is an electronic musical instrument designed to produce artificially generated sound, using techniques such as additive, subtractive, FM, physical modelling synthesis, or phase modulation to create sounds.

History and Introduction to Synthesizers

These resources are useful as a starting point for history and information about synthesizers:

• Wikipedia entry on Synthesizers
• Thomas Kolb’s Introduction to Synthesizers