This is extract from the documentary 'Knots and Fields' by Andrew Chesher and David Ryan (2010). The full documentary is 75 mins in length and looks at the history and the contemporary relevance of the famous Summer Courses in New Music which have been held in Darmstadt, Germany since 1946. It was here that composers such as Boulez and Cage among many other key figures in modern music met in the 50s and 60s.
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