Flange Comb Filter Parameters

The flange simulation is a feedforward comb filter, where the delay $M(n)$ is a function of time,

$$y(n) = x(n) + gx(n-M(n)).$$

• coefficient $g$ (DEPTH parameter), determines the prominence of the flanging effect.

• flange is typically swept from a few milliseconds to 0 to produce characteristic ``flange'' sound.

The time-varying delay can be handled by modulating $M(n)$ with a low-frequency oscillator (LFO) sinusoid:

$$M(n) = M_0[1 + A\sin(2\pi fnT)],$$

where

$$f \triangleq$$ rate or speed of the flanger, in Hz

$$A \triangleq$$ ``excursion'' (maximum delay swing)

$$M_0 \triangleq$$ average delay length controlling the

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