THE ELECTRONIC WORKS OF GYÖRGY LIGETI AND THEIR ...

fact that the arching middle section (Section F and its retrograde) was coherent, and that
the final F Section was filtered, letting the retrograde of Section A come through clearly.
The symmetry was blurred, however by the disruptive filtering of the second half, the
anomaly areas, and the presence of both prime, retrograde, and invariant figures in the
second half.
One finds a later example of this symmetrical form in Ligeti’s organ piece,
Harmonies (1967). The pitch structure of Harmonies is highly symmetrical, and, as can
be seen in Figure 4.11, the expanding, then contracting shape is highly reminiscent of the
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ring-modulated gestures in Glissandi itself. This piece is analyzed by Pozzi Escot, who
points out a number of other symmetrical parings such as finger pairings for the organist’s
hands through striking visual representations.
What Escot does not mention in her article is that this symmetry is also distorted.
Ligeti provides a full page of instructions on how the organ is to be prepared, including
any number of ways to reduce wind pressure to the pipes. One section of this score,
labeled, “fluctuation of intonation and dynamics,” states that,
Half-drawn stops, half-depressed keys, and pipes (especially reeds) that do not
speak properly due to too little wind pressure all cause fluctuations of dynamics
and intonation (micro-intervals, glissandos, etc.). ‘Impurities’ of this kind are
welcome in realizing the piece; they contribute further to the denaturing the tone
colours. The notated pitches in the musical text, then, refer only to the keys to be
depressed or held; the succession of pitches that actually results can fluctuate
freely; the ‘harmonies’ are ‘tainted’ and more or less diverge from the written
text. 29
28
Pozzi Escot, “‘Charm’d Magic Casements,’ Mathematical Models in Ligeti” Sonus 9, no. 1, 17-37.
29
György Ligeti, Zwei Etüden für Orgel (Mainz: B. Schotts Söhne, 1969), 4.
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