In the "Chamber Concerto" (1969–70), several layers, processes and kinds of movement can take place on different planes simultaneously. In spite of frequent markings of "senza tempo", the instrumentalists are not given linear freedom; Ligeti insists on keeping his texture under strict control at any given moment. The form is like a "precision mechanism". Ligeti was always fascinated by machines that do not work properly and by the world of technology and automation. The use of periodic mechanical noises, suggesting not-quite-reliable machinery, occurs in many of his works. The scoring is for flute (doubling piccolo), oboe (doubling oboe d'amore and cor anglais), clarinet, bass clarinet (doubling second clarinet), horn, trombone, harpsichord (doubling Hammond organ), piano (doubling celesta), and solo string quintet.