In
music, a pulse is a series of identical, yet distinct
periodic short-duration
stimuli perceived as points in
time (DeLone et al. (Eds.), 1975, chap. 3). Ideally, this is opposed to a series of identical but aperiodically occurring stimuli, a series of periodically occurring yet otherwise differentiated stimuli, or an uninterrupted stream of sound (such as a
drone). A pulse may be an unheard event underlining a piece or
metric level, thus the
tempo of the piece is how fast the pulse is running, implied by the performer or listener based on context or past experience, or audible such as in
Terry Riley's
In C.
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