A measure of the relative degree of concordance / discordance of a musical interval.
Joe Monzo and other tuning theorists have adopted the single term accordance, in agreement with the assertion made by many music theorists that, rather than describing two diametrically-opposed sensations, concordance and discordance refer instead to the opposite poles of a single continuum of sensation.
It is important to note that accordance is determined strictly on the basis of psychoacoustic phenomona, which differentiates it from the related concept of sonance. The latter is usually determined not merely as an auditory phenomenon, but rather as a result of musical context, highly dependent on the style of a particular composer or era.
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