Short for
synthesizer, a synth is a keyboard-type intstrument that can be programmed to play any type of sound imaginable. Most commonly,
synths are programmed to sound like electronic keyboards. Used properly, as by Pete
Townsend or Rich Wright synths can be pleasing and add depth to a song. However, used improperly, synths can make a song sound cheesy, for example, like in much eighties music.