AMM music is supposed to admit all sounds but the members of AMM have marked preferences. An open-ness to the totality of sounds implies a tendency away from traditional musical structures towards informality. Governing this tendency -reining it in- are various thoroughly traditional musical structures such as saxophone, piano, violin, guitar, etc., in each of which reposes a portion of the history of music. Further echoes of the history of music enter through the medium of the transistor radio (the use of which as a musical instrument was pioneered by John Cage)”  Cornelius Cardew, Towards an Ethics of Improvisation