Harmonic Vocabulary in the Music of John Adams: A Hierarchical Approach

Following the minimalist tradition, much of John Adams's' music consists of long passages employing a single set of pitch classes (pcs) usually encompassed by one diatonic set.2 In many of these passages the pcs form a single diatonic triad or seventh chord with no additional pcs. In other passages textural and registral formations imply a single triad or seventh chord, but additional pcs obscure this chord to some degree. These phenomena suggest a hierarchical approach to the harmonic analysis of Adams's music that relates passages containing only a triad or seventh chord to passages incorporating additional pcs. For each individual passage I recognize three distinct pc levels arranged in an ordered triple of pc sets called a complex. A complex consists of (1) a chord-a strongly projected triad or seventh chord; (2) a sonority-all strongly presented pcs in the passage, encompassing the chord plus other strongly presented pcs, if any; and (3) a field-a complete diatonic collection plus strongly presented non-