Influences of the Electronic Music Procedures on Ligeti's Instrumental Works

In his essay Musique et Technique, originally published in a compilation called Rückblick in die Zukunft^1.19 Ligeti relates that when two of his orchestral compositions Atmosphères and Apparitions were first performed, in 1961 and 1960, several listeners thought there were loudspeakers disseminated in between the performers.

The illusion was caused by the composer using techniques he already worked on in the Electronic Music Studio of Cologne, techniques he succesfully adapted to instrumental music.

He calls that specific technique the ``timbre of motion''.

[...] by getting below the threshold of ``fusion''^1.20we obtain modifications of the structure of the musical texture and we get instrumental combinations which are sensibly different from those obtained by using the conventional instrumental combination techniques.

In the mentionned article, he first uses the term micropolyphony:

Already from 1950 I was imagining new timbres, a ``static'' musique, ``sound spaces''^1.21

In Budapest, 1956, before my electronic music studio experiences I composed a piece called Viziók (Visions) which later became the first movement of Apparitions.

[...]

I applied those experiences to orchestral music, in 1959 in a really different way to the second movement of Apparitions right after my stay in Cologne. In the first movement the sound spaces were still static and aligned as successive blocks while, in the second movement, for the first time, the destabilization of those blocks appeared as well as textures modifications and the micropolyphony.

[...]

The experiences made in the studio of electronic music by using the ``melting of succession''^1.22 and by stacking a great number of independently elaborated sounds and sound sequences on top of each other, made me imagine a kind of complex polyphony created by musical textures and networks. I called this way of composing micropolyphony because the many rhythmical elements were getting below the threshold of fusion in the polyphonic texture.

The texture gets so dense that the parts can not be perceptible anymore in their own individuality and we can apprehend the whole only as a ``whole'', from a higher perception level.