During the winter of 1969/70, while I was realising my electronic piece Sinophony – named for its extensive use of sine tones as sound material – I had the idea of making another piece in which not only the sound but also its shaping would be achieved by sine curves. This led to Sinophony II, which after some attempts with a synthesizer in the electronic studio of the Cologne Music University in the spring of 1971 was finally realised with the help of a computer during the last fourteen days of 1972 in the studio of the EMS Foundation Stockholm.

Sinophony II is not a “piece” in the usual sense but a piece of a tone world, in which every tone moves according to fixed laws from the beginning to the end of the presentation (and beyond) along its own path, which is determined by the individual given freedom of the tone in its environment. This recording, which with its range of 10 octaves, 25 minutes and 60 decibels had to be adapted to the limitations of common tape-recorders, presents an excerpt of the course taken by over 400 simultaneous tone-paths moving under the controlling influence of well over 800 temporally concurrent sine curves.

The building block of the whole is the FIFTH, in other words the relationship 2:3, which forms the basis of the three domains pitch, loudness and duration.

On a formal level the piece consists of eight completely independent layers running parallel in time, each of them based on an infinite series of similarly shaped, internally hierarchical tone groups: in each group the individual tones form in their pitch a sort of overtone series “squashed” to about seven-twelfths of the natural overtone series (with the lowest interval thus a fifth instead of an octave) and the amplitude of every tone is two-thirds of the next one lower down. The interval between the tone-groups, measured from their lowest tones or “tonics” (one of which is the frequency 1 Hz), is five fifths.