Music for Magnetic Tape and Solo Piano - Andrzej Dobrowolski
Written in 1971-72 for Zygmunt Krauze, this composition was premiered in February 1972 in Warsaw. As Zygmunt Krauze was recording the piece for the BBC in London at exactly the same time, the piano part was performed by Andrzej Dutkiewicz. Formally speaking, the work resembles an instrumental concerto, the solo part being opposed to the tape part. The piano part is precisely notated except for an improvised section, for which only the principles of improvisation are listed. The tape was produced at the Experimental Studio of the Polish Radio in Warsaw, with the technical support of Bohdan Mazurek. The original tape material consists exclusively of piano sounds: 1) trills with and without pedal; 2) trills performed with piano strings dampened with Plasticine; 3) fast irregular passages with piano strings dampened with Plasticine; 4) tremolos performed with a thin metal rod on the strings; 5) short strokes executed with wooden and metal rods on the strings. is initial material was submitted to far-reaching transformations (transpositions, overlapping of various progressions, filtration, application of a ring modulator, imposing the rhythmic pattern of one progression on others, application of an envelope generator, and so forth).
(from the 1987 Warsaw Autumn programme book)