Prepared guitar

A prepared guitar is a guitar that has had its timbre altered by placing various objects on or between the instrument's strings, including other extended techniques. This practice is sometimes called tabletop guitar, because many prepared guitarists do not hold the instrument in the usual manner, but instead place the guitar on a table to manipulate it.

The idea of altering an instrument's timbre through the use of external objects has been applied to other instruments as well, most notably John Cage's prepared piano, which preceded the prepared guitar.

With prepared guitars, however, one of the key goals in preparing the instrument is changing its timbre – the fundamental tone composition of the sound. This is typically achieved by placing objects on or under the strings. The objects can have a tone of their own, like for instance a pen spring, but can also cause strange string resonance effects or behave like a seesaw and create echoing or buzzing effects after being struck and swinging like a balance. Many of the sounds sound more or less like clocks, bells or Non Western musical instruments or even non string percussion instruments.

The history of Norwegian composer and guitar player Bjørn Fongaard (1919–1980) probably marks the first steps into prepared guitar. He started off by constructing a quarter tone guitar with adaption of the fretboard, but very early left this in favour of a diverse set of prepared guitar techniques. His first pieces in this genre came in the mid 60's.

The method of actually preparing the guitar was developed in the late 1960s by Keith Rowe, in imitation of Jackson Pollock's painting method and John Cage's prepared piano. Rowe developed various prepared guitar techniques: placing the guitar flat on a table and manipulating the strings, body and pickups in unorthodox ways to produce sounds described as dark, brooding, compelling, expansive and alien. He has been known to employ objects such as a library card, rubber eraser, springs, hand-held electric fans, alligator clips, and common office supplies in playing the guitar.

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