George Crumb (born October 24, 1929) is an American composer of modern and avant garde music. He is noted as an explorer of unusual timbres. Examples include spoken flute (one speaks while blowing into the instrument) and glass marbles poured onto an open piano. After initially being influenced by Anton Webern, Crumb became interested in exploring unusual timbres. He often asks for instruments to be played in unusual ways and several of his pieces are written for electrically amplified instruments.