The term Unplugged has come to refer to music that would usually be played on amplified instruments (such as an electric guitar or synthesizer) but is rendered instead on instruments that are not electronically amplified, for example acoustic guitar or traditional piano, although a microphone is still used.
The word became incorporated into the title of a popular MTV series that began in the 1989/1990 US TV season, MTV Unplugged, on which musicians performed acoustic or "unplugged" versions of their familiar electric repertoire. Many of these performances were subsequently released as albums, often featuring the title Unplugged.
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