The starting point in the formation of the concert program of the modern music ensemble Klangforum Wien (Austria) was the reflection on the theme of musical geometry in the music of the XX and XXI centuries, namely the interaction of layers and lines, horizontal and vertical thinking, which plays a fundamental role in Austro-German musical culture. The powerful polyphonic tradition ("games of pure mind"), coming directly from J.S. Bach and then reaching a new stage in the discoveries of the Second Viennese School (German: Neue Wiener Schule), finds its development both in the works of representatives of the post-war avant-garde and in the works of contemporary composers. As a free musical fantasy on this theme, the ensemble presents a program of works by A. Webern, K. Stockhausen, D. Ligeti, B. Furrer and K. Lang.