reson~ Bandpass filter controllable by center frequency and Q Bandpass filter controllable by center frequency and Q. reson~ implements the following filter equation: y[n] = gain * (x[n] - r * x[n-2]) + c1 * y[n-1] + c2 * y[n-2], where r, c1, and c2 are parameters calculated from the input center frequency and Q. Q is the filter bandwidth divided by center frequency. Inputs can be floats or signals. The specification is similar to the nres unit generator in cmusic.

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