89 lines
1.6 KiB
Racket
89 lines
1.6 KiB
Racket
#lang scribble/manual
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@(require (for-label racket))
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@title{Resonz}
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Resonant filter.@section{related}
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Classes/Formlet, Classes/RHPF, Classes/RLPF, Classes/Ringz
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@section{categories}
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UGens>Filters>Linear
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@section{description}
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This is the same as link::Classes/Ringz:: , except that it has a constant gain at 0 dB instead of being constant skirt.
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It is a two pole resonant filter with zeroes at
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@racketblock[
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z = ±1
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::
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Based on emphasis::K. Steiglitz, "A Note on Constant-Gain Digital Resonators", Computer Music Journal, vol 18, no. 4, pp. 8-10, Winter 1994::.
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]
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@section{classmethods}
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@section{method}
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ar, kr
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@section{argument}
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in
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The input signal.
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@section{argument}
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freq
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Resonant frequency in Hertz.
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WARNING: due to the nature of its implementation frequency values close to 0 may cause glitches and/or extremely loud audio artifacts!
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@section{argument}
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bwr
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Bandwidth ratio (reciprocal of Q). rq = bandwidth / centerFreq.
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The reciprocal of Q is used rather than Q because it saves a
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divide operation inside the unit generator.
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@section{argument}
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mul
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Output will be multiplied by this value.
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@section{argument}
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add
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This value will be added to the output.
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@section{Examples}
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@racketblock[
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{ Resonz.ar(WhiteNoise.ar(0.5), 2000, 0.1) }.play
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// modulate frequency
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{ Resonz.ar(WhiteNoise.ar(0.5), XLine.kr(1000,8000,10), 0.05) }.play
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// modulate bandwidth
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{ Resonz.ar(WhiteNoise.ar(0.5), 2000, XLine.kr(1, 0.001, 8)) }.play
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// modulate bandwidth opposite direction
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{ Resonz.ar(WhiteNoise.ar(0.5), 2000, XLine.kr(0.001, 1, 8)) }.play
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::
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]
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