ABSTRACT
This chapter explores how small- and large-scale rhythmic and metrical transformations may be understood. Augmentation is a rhythmic variation in which the duration of each note value is increased by a common factor, and diminution is a rhythmic variation in which the duration of each note value is decreased by a common factor. Metrical upshifting is a transformation in which the fastest consistent pulse changes to a new, faster pulse layer within the same metrical consonance. Changes in the sounding meter can involve grouping dissonances, displacement dissonances, upshifting, or downshifting. Loosening is the process of moving from one displacement dissonance to a loose relative of that dissonance, and as carries with it a sense of deceleration. Tempo Modulation is a simultaneous change to both the sounding meter and the tactus in which a pulse layer other than the tactus from the old meter remains constant and becomes a layer of the new meter.
