The barrel organ, sometimes called the street organ or organetto di Barberia in honour of its inventor Giovanni Barbieri, who devised it in 1702, is a mechanical musical instrument built from a series of pipes and a bellows, much like a small organ. Its sound is produced by a rotating cylinder, studded with pins or pegs, each positioned to trigger a particular note.

The pipes are usually made of wood, though sometimes of metal, and the whole instrument is enclosed in a wooden sound box, often carved and richly decorated.

Turning a metal crank causes the cylinder to rotate, so that the pins lift levers which open the valves of the pipes, allowing air from the bellows to pass through and make them sound. While cranking, the player also feeds in a perforated cardboard roll: as it passes through the mechanism, the holes are “read” and translated into music. A huge repertoire of these rolls survives, ranging from lively dance tunes to famous works of classical and modern music.

The barrel organ has long been a familiar presence in town squares and marketplaces, particularly in Northern Europe, where its cheerful melodies bring colour and charm, delighting both children and adults. Among the best-known performers is the French musician Pierre Charial, while composers such as the German clarinettist Michael Riessler have written original music for the instrument.