Metrical Dissonances
Matthew Santa · 2019
This chapter aims to define what it means for music to be metrically consonant or dissonant. There are two kinds of metrical dissonances: displacement dissonances and grouping dissonances. A grouping dissonance is one in which two conflicting pulse layers are moving at different speeds, and the faster layer is not simply a multiple of the slower layer. One must be careful not to make the mistake of equating the number of dots in each layer of a dot diagram with the numbers in the label of the dissonance. A subtactus-level dissonance is one in which the dissonance can be expressed entirely within one pulse of the tactus, while a hypermetrical dissonance is one in which the dissonance can only be expressed over multiple measures of the notated score. Direct metrical dissonances are those in which two conflicting layers are presented simultaneously, while indirect metrical dissonances are those in which two conflicting layers are presented in immediate succession.