Text: It is of interest to notice that the eleventh and twelfth harmonics, of frequencies 2827 and 3084 respectively, are both stronger than the fundamental note of frequency 257, and as the ear is many times more sensitive to notes of the higher frequencies than to notes of the lower, the sound which the ear perceives must consist almost entirely of tones of these higher frequencies. In other words, the eleventh and twelfth harmonics are composed almost entirely of beats of the lower frequncies. Thus the eleventh and twelfth harmonics are referred to as the "beat harmonics".

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