A Reconsideration of
IntervalClass Spacethrough the Perspective of Joseph Straus’s Evenness and
Spaciousness
In his 2005 article, Joseph Straus’s ‘offset number' derived from his ‘fuzzy transformational voice leading’ implies ic 6 as the most “even, spacious” ic among ics 1 to 6 (2005, 67). However, to define ic 6 as the most even, we must locate it in the larger space of an octave, for it equally divides an octave into two even halves. But the ic representing an octave—ic 0 — is missing in Straus’s discussion. To satisfy Straus’s notion of evenness, we must consider ic 0. However, how do we know ic 0 only ever represents an octave? Also, once we consider ic 0, ic 6 no longer projects the most spacious ic, for ic 0— the octave— has a bigger space than that of ic 6. Prompted by this paradox, I propose a theory reconceptualizing the space of all ic’s. I set up two rules to measure the space of all ic’s in a clockimage used by
most theorists to represent a pcspace: (1) no pc ever remains stationary, and
(2) we measure the shortest distance between two pcs. These two rules allow us to perceive ic 0 as
the most spatial ic projected by the full circle progression around the clock,
and ic 6 as the most even ic dividing the clock into two equal
semicircles. Based on this new
definition of the space of all ics, I refine Straus’s ‘offset number’, which
reveals a truer picture of the ‘degree of chromaticness’ of a chord. To show the practical advantage of my
harmonic measurement, my presentation concludes with analyses of Kürtag’s Chamber
Song Op. 37 and Crawford’s String Quartet.
