THE ELECTRONIC WORKS OF GYÖRGY LIGETI AND THEIR ...

each sound by reckoning the total number of positives minus the number negatives will
describe an aspect of the sound as a whole. While in many cases this turns out to be true,
it is not necessarily the case, as sounds could contrast in every single opposition and still
reckon to identical sums–take for example the trivial case where 12 oppositional
categories are active and a sound occurs that is negative for all the even categories and
positive for all the odd; a corresponding sound that is positive for all the even categories
and negative for all the odd would be maximally contrasting, yet receive an identical
rating. I will follow Cogan in his later work, which discusses specific oppositions or
combinations of oppositions as more distinct without this kind of attempt to normalize
individual sounds.
While similarity in one oppositional category is often enough to create some
degree of similarity between two sounds, the consistent grouping of specific oppositions
consistently will provide for the creation of larger categories of sound-types which can
undergo more refined transformations. Typical instrumental timbres, which are often
taken as being related, and used to perceive different polyphonic strands can be described
by groups of oppositions. Pizzicato, for example, has a specific attack characteristic and
noise content which allows a listener to follow a line–even between families of string
instruments, over different registers, and so forth. Moreover various configurations of
sine tones can all share the properties of being compact, containing a similar number of
partials with similar spacing; if these configurations are consistently a part of the piece,
nuances of the spacing, such as the division into harmonic, sub-harmonic and non-
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