In signal processing, a comb filter adds a delayed version of a signal to itself, causing constructive and destructive interference. The frequency response of a comb filter consists of a series of regularly spaced notches, giving the appearance of a comb. Wikipedia, Comb Filter
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See Also
Additive and Subtractive Synthesis band-pass filter Bessel Filter Butterworth Filter High-Pass Filter Law of Molecular Synthesis and Combination - Organic Low-Pass Filter synthesis synthesizer