Scene designer and robot artist Roland Olbeter developed and crafted the unique ensemble "The Sound Machines," an automated, electrical string quartet with a drum. The four string instruments sound and function like electric guitars, the difference being that each sound machine only has one string.
21 micro-cylinders from Festo are used in each sound machine. The micro-cylinders imitate the mechanical movements of a musician's left hand on the string instruments, determining the pitch of the tone by changing the length of the strings. Various drumsticks and a jazz brush are moved on the drum by micro-cylinders.
"Fast Blue Air," the music composed especially for the Hanover Fair by Australian composer Elena Kats-Chernin, explores the range of sounds generated by the sound machines including the noises produced by the pneumatics.