Text: When beats arise between the fundamentals of two compound tones, the dissonance will in general be harsher than between two simple tones of the same pitch, for in the former case each pair of overtones may beat also. Supposing for example, the two fundamentals to be B1 and C, the diagram shows the dissonant overtones. The harshness of the beats between each pair of overtones in the diagram, must be estimated in the case of simple tones, for these overtones are simple tones; but in estimating the total harshness of the whole combination, it should be remembered that for ordinary qualities of tone, the intensity of the partials becomes less and less as we go farther from the Fundamentals (a fact roughly indicated in the diagram by the use of smaler type for the upper partials); and therefore the intensity of the beats will become less and less as we ascend. Nevertheless, these higher partials are always there even though we may not hear them or be able to measure them both going up and going down.

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