Fifteenth

Fifteenth

In music, a fifteenth or double octave, abbreviated 15ma, is the interval between one musical note and another with one-quarter the wavelength or quadruple the frequency. The fourth harmonic, it is two octaves. It is referred to as a fifteenth because, in the diatonic scale, there are 15 notes between them if one counts both ends (as is customary). Two octaves (based on the Italian word for eighth) do not make a sixteenth, but a fifteenth. In other contexts, the term two octaves is likely to be used.

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Famous quotes containing the word fifteenth:

    I too mean to be out of politics. The ratification of the Fifteenth Amendment gives me the boon of equality before the law, terminates my enlistment, and discharges me cured.
    Rutherford Birchard Hayes (1822–1893)

    It could be clearly proved that by a practical nullification [by the South] of the Fifteenth Amendment the Republicans have for several years been deprived of a majority in both the House and Senate. The failure of the South to faithfully observe the Fifteenth Amendment is the cause of the failure of all efforts towards complete pacification. It is on this hook that the bloody shirt now hangs.
    Rutherford Birchard Hayes (1822–1893)