Merge pull request #506 from andrewcsmith/patch-2
[supercollider.git] / HelpSource / Classes / Resonz.schelp
blobb2c1d58f1fced971360853c9995c44f544e26e03
1 class:: Resonz
2 summary:: Resonant filter.
3 related:: Classes/Formlet, Classes/RHPF, Classes/RLPF, Classes/Ringz
4 categories::  UGens>Filters>Linear
7 Description::
9 A two pole resonant filter with zeroes at
11 code::
12 z = ±1
16 Based on  emphasis::K. Steiglitz,  "A Note on Constant-Gain Digital Resonators", Computer Music Journal, vol 18, no. 4, pp. 8-10, Winter 1994::.
19 classmethods::
21 method::ar, kr
23 argument::in
25 The input signal.
28 argument::freq
30 Resonant frequency in Hertz.
33 argument::bwr
35 Bandwidth ratio (reciprocal of Q). rq = bandwidth / centerFreq.
38 The reciprocal of Q is used rather than Q because it saves a
39 divide operation inside the unit generator.
42 argument::mul
44 Output will be multiplied by this value.
47 argument::add
49 This value will be added to the output.
52 Examples::
54 code::
56 { Resonz.ar(WhiteNoise.ar(0.5), 2000, 0.1) }.play
58 // modulate frequency
59 { Resonz.ar(WhiteNoise.ar(0.5), XLine.kr(1000,8000,10), 0.05) }.play
61 // modulate bandwidth
62 { Resonz.ar(WhiteNoise.ar(0.5), 2000, XLine.kr(1, 0.001, 8)) }.play
64 // modulate bandwidth opposite direction
65 { Resonz.ar(WhiteNoise.ar(0.5), 2000, XLine.kr(0.001, 1, 8)) }.play