- Logarithmically-spaced Dirac comb
Like the standard
Dirac comb , the logarithmically-spaced Dirac comb consists of an infinite sequence ofDirac delta function s. In the case of the logarithmically-spaced comb, these are spaced in octave intervals, i.e., the delta functions are placed at positions , for all integers .In
music al applications, this type of Dirac comb can be used to create a 12-note scale that spans the infinite space of octaves. Such a log-spaced Dirac comb, with perhaps a Gaussian weighting, when ascending or descending, gives the well knownShepard tones effect of a sound which is perceived as though it is forever going up or down in pitch.
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