Text: Dissonance between similar tones varies in intensity from 33 beats per second (maximum). The points of least dissonance are the places where the numbers expressing the RATIO of the two rates of vibration are SMALL WHOLE NUMBERS. Beats cause dissonance. A sound which is unstable, more active, and which needs to resolve to a consonant interval is called dissonance. The dissonant intervals are as follows: the augmented and diminished intervals, the major and minor seconds and sevenths, and the perfect fourth, when not supported by a third or a perfect fifth below it.

See Also: RATIOS, BEATS, DIFFERENCE TONES, RESULTANT TONES, SUMMATION TONES, DIFFERENTIATION, TRIPLE CURRENTS, HARMONY

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