The Free Music Machine was a machine that controlled the pitch, volume and timbre of eightoscillators.Two large rollers fed four sets of paper rolls over a set of mechanical arms that rolled over the cut contours of the paper and controlled the various aspects of the oscillators.

The 'Free Music Machine' was created by musician and singerBurnett Cross and the Australian composer Percy Grainger. Graingera virtuoso Pianist and pupil of Busoni, had been developing his ideaof "free music" since 1900: based on eighth tones and completerhythmic freedom and unconventionally notated on graph paper.Grainger had experimented using collections of Theremins andchanging speeds of recorded sounds on phonograph disks andeventually developed his own instruments. Graingers experimentswith random music composition predated those of John Cage by 30years with "Random Round" written in the 1920's.Graingers first experiments used a Pianola "player piano" controlling three Solovoxes by means of strings atached to the Pianola's keys,this combintaion was abandoned as it was not possible to create acontinuous glissando effect from the Pianola. Grainger started workon a more elaborate but eccentric machine in collaboration with Burnett Cross and his wife, Ella Grainger.