Conventional wisdom holds that the cadenza is a musical parenthesis. Like linguistic parenthetical remarks, cadenzas may be engaging, illuminating, and insightful, but they are not regarded as intrinsic to structural coherence. Perhaps for this reason, the topic has remained parenthetical in modern music theory discourse. Despite the connotations this neglect implies, the cadenza tradition stands as one endowed with great musical richness, worthy of further analytic investigation.
This article seeks to define the dual function of the cadenza. Specifically, the cadenza is heard simultaneously as a local, harmonic event and as a global, formal event. On the local level, it may either prolong one harmony or progress from one to another. On the global level, it can serve a variety of formal functions: highlighting salient cadences; opening a space for virtuosic display; and developing, relating, and rehearing elements of the concerto movement proper.
The cadenza's dual function grants it a potential far exceeding the simple characterization as parenthesis. Skillfully composed cadenzas exploit the tension between local and global functions and can initiate subtle yet profound rehearings of music outside cadenza space—rehearings that give us pause to reconsider both the cadenza-as-parenthesis metaphor and the artificial boundaries we construct among composer, performer, and analyst.