orchestral percussion instrument resembling a small upright piano, patented by a Parisian, Auguste Mustel, in 1886. It consists of a series of small metal bars (and hence is a metallophone) with a keyboard and a simplified piano action in which small felt hammers strike the bars. Each bar is resonated by a wooden box or similar chamber tuned to reinforce the fundamental harmonic (component tone) of the bar. A pedal lifts a felt-pad damper from the bars, permitting use of either sustained or short notes. The normal range is four octaves upward from middle C.