Apparently Imperfect: On the Analytical Issues of the IAC

This article examines the analytical nuances of the imperfect authentic cadence (IAC). Whereas the cadential hierarchy currently in use in most North American textbooks suggests in no uncertain terms that it is stronger than the half cadence (HC) and weaker than the perfect authentic cadence (PAC), its appearances in the musical literature have often been far more nuanced, as illustrated by the frequency with which the IAC functions in a manner that contradicts the standard theoretical formulation. The IAC’s ability to engage with these alternative functions results in a range of cadential strengths, giving rise to possibilities for ambiguities, reinterpretations, and conflicts that in turn may set the stage for fascinating expressive and narrative twists.