From the notes for this edition:"The piece is performed by one pianist and three assistants.The pianist plays the scales continuously in...(a prescribed order)..then starts the cycle all over againÂ...While the pianist is playing three assistants prepare the piano according to the table, with three different materials A: long resonance (e.g. metal screws, etc.), B: short resonance (e.g. paper, plastic, cork, etc.), C: mute (with material such as sponge placed between the hammer and the string).The pianist plays (until) the instrument becomes mute. When none of the keys produces a sound, he plays some more scales and that is the piece's end."