Two of the three sound layers A, B and C are to be reproduced as playback (the playback on the included CD offers an alternative): - First, sound layer B is recorded on tape. - All four instruments are then to be tuned one quarter-tone highter during the following recording of sound layer A. - Sound layer C is to be played live. Of the three ad libitum coloured light parts, Luce 1 and 2 correspond to sound layers A and B, Luce 3 to sound layer C.