Subharmonic series

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Undertone series

The subharmonic series (or undertone series) is a sequence of notes generated by unit-fraction frequency ratios under a fundamental: 1/1, 1/2, 1/3, 1/4, 1/5, 1/6, 1/7... ad infinitum. Each member of this series is a subharmonic; the term undertone, which is not an exact synonym, is also used in the same sense by many people (especially because undertones are rarely conceived as partials of a sound's timbre).

See also

• Harmonic series