The term “Avant Garde” (read “advance group”) was synonymous with the “free” jazz of the 1960s in which the performer spontaneously chose his own musical path rather than follow any traditional rules. The music challenged the listener as all aspects of performing were at the discretion of the improviser. The music often ignored recognizable pitches, rhythms and musical shapes, allowing moans and cries, etc. to convey musical energy.
Art Ensemble of Chicago