What is having or indicating, equal tones, or tension. Isotonic system (Mus.), a system consisting of intervals, in which each concord is alike tempered, and in which there are twelve equal semitones called?

isotonic — Having or indicating, equal tones, or tension. Isotonic system (Mus.), a system consisting of intervals, in which each concord is alike tempered, and in which there are twelve equal semitones. (Webster's 1913.)

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