Enormous technical requirements make John Cage's "Etudes Boreales" a highly virtuosic work, which requires an extreme sensitivity of feeling for the coordination of fingers, instrument, and intellect. On this CD it is presented in versions: for piano solo and later for cello solo with piano solo. As in the sister works, "Etudes Australes" and "Freeman Etudes", Cage based the "Etudes Boreales" on a star chart. He used the chart of the northern sky that the Czech astronomer Antonín Bečvář made in 1962. The time length piece 26'1.1499' - Friedrich Gauwerky chooses the first 640.3 seconds for this recording, thus giving the piece the titel 10'40.3' - documents the composer's retreat from an intentional determination of the sounds. And also the "Harmonies" welcome the creative possibilities of whatever happens next.