THE ELECTRONIC WORKS OF GYÖRGY LIGETI AND THEIR ...

glissandi end, and an area of low white noise begins. IIIk occurs one second away from a
large reiteration of this noise, yet these spots fall on either side of the large cut-off of the
upper-middle register and introduction of the highest register which define Event 5. Event
6 corresponds to III-l, and the following divisions, IIIm-IIIo may correspond to some of
the clipping within Event 6, which clearly displays the same acceleration towards the
midpoint.
Ligeti articulates these points of his rhythmic design largely by the introduction of
new materials or new registers; as in Section B, the introduction of materials proceeds
slowly at first, and then accelerates towards increased density. Events 1 and 2 prepare this
process, as they are the longest events and introduce only slow moving material, while
Events 3-6 bring it to its culmination, compressing the number of events per second and
also accelerating the previous material to bring this third stage of accretion to its peak.
Event 1 contains only the invariant gestures introduced in Section E and a slow
sine tone glissandi, and thus provides a smooth transition from the previous section. The
invariant gestures share the same center frequencies as those in Section E, and as they
gradually merge with other material in Event 2, they disappear when this transition is
complete. The only new material in Event 1 are the low sine glissandi which occupy the
register between 50 and 170 Hz. Event 2 transfers these slow glissandi to the area
between 400 and 680 Hz, introducing faster glissandi in the area below 400 Hz. Event
two also presents more angular glissandi of filtered noise in the range from 735 to 1459
Hz, the range above the newly introduced glissandi, and that previously occupied by the
invariant gestures.
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