THE ELECTRONIC WORKS OF GYÖRGY LIGETI AND THEIR ...

flush out Morris’s general category for “internal agitation.” The oppositions of
level/oblique and steady/wavering deserve special clarification. The first of these refers to
whether the pitch of a note is fixed or noticeably moving; thus a glissando would be
oblique. Steady/wavering refers to the more internal aspects of a sound, so that the use of
vibrato, which Randall earlier cited as an area of timbre in need of refinement, could be
cited here as an example of wavering. The final oppositions also deal with internal
agitation; sustained/clipped deals with the internal disruption of a sound–whether it is
intermittent, like a tremolo, or continuous. Beatless/beating describes the presence of
acoustical beats caused by minor disturbances such as conflicting sound waves that differ
by a small number of Hertz; this opposition and the final which describes the speed of
these beats, should they be present, are of use in a limited number of cases.
Both Cogan and Jakobson emphasize the importance of taking these categories in
the proper context. In a linguistic setting, not every oppositional category will have the
power to change one phoneme to another; in some languages a shift from a back vowel to
a front vowel may be perceived as an invariant–a matter of accent with no effect on
meaning–while in others languages such as shift may correspond to a change verb tense or
mood, and thus a significant alteration of meaning. To help ensure an appropriate context,
I have, at times, made a few changes in the table of oppositions. First, I have added
categories for channel mixture (in the analysis of Artikulation) and reverberation. While
not strictly an aspect of timbre, the use of the spatial orientation of sound sources is
included in both Randall and Morris’s lists, and has a very significant effect on what we
perceive as musically coherent. This will be particularly evident in Artikulation–originally
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