Title: Linear Verticalities
Description: This dissertation aims to shed light on aspects of harmonic construction in Georges Aperghis' Contretemps, a twenty-minute composition for soprano and large ensemble. The foundation of this analysis is the hypothesis that the piece is governed by emblematic intervallic aggregations while their linear and vertical hypostases are inextricably intertwined with each other, formulating global axioms for the harmonic construction of the piece. Through a series of reductions and prolongational analyses, the research explores the role of the linear pitch aggregations articulated in various instrumental combinations. This analysis uses Allen Forte's pitch-class set theory for the representation of the intervallic structures, while 24-tone equal temperament (24-TET) serves as a point of reference in organizing the chromatic and microtonal pitch aggregations. The continual fusion of chromatic and microtonal entities forges a saturated soundscape with, sometimes, indiscernible chordal constructions.

Multiple overlapping perspectives are possible concerning the global intervallic axioms that underline and determine distinct archetypes of chordal structures in the work.