Pitch is the perceived fundamental
frequency of a
sound. While the actual fundamental frequency can be precisely determined through physical measurement, it may differ from the perceived pitch because of
overtones, or
partials, in the sound. The human auditory perception system may also have trouble distinguishing frequency differences between notes under certain circumstances. According to
ANSI acoustical terminology, it is the auditory attribute of sound according to which sounds can be ordered on a scale from low to high.
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