HelpSource/Classes/Resonz.schelp

   1 class:: Resonz
   2 summary:: Resonant filter.
   3 related:: Classes/Formlet, Classes/RHPF, Classes/RLPF, Classes/Ringz
   4 categories::  UGens>Filters>Linear
   5
   6
   7 Description::
   8
   9 A two pole resonant filter with zeroes at
  10
  11 formula::
  12 z = ±1
  13 ::
  14
  15
  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::.
  17
  18
  19 classmethods::
  20
  21 method::ar, kr
  22
  23 argument::in
  24
  25 The input signal.
  26
  27
  28 argument::freq
  29
  30 Resonant frequency in Hertz.
  31
  32
  33 argument::bwr
  34
  35 Bandwidth ratio (reciprocal of Q). rq = bandwidth / centerFreq.
  36
  37
  38 The reciprocal of Q is used rather than Q because it saves a
  39 divide operation inside the unit generator.
  40
  41
  42 argument::mul
  43
  44 Output will be multiplied by this value.
  45
  46
  47 argument::add
  48
  49 This value will be added to the output.
  50
  51
  52 Examples::
  53
  54 code::
  55
  56 { Resonz.ar(WhiteNoise.ar(0.5), 2000, 0.1) }.play
  57
  58 // modulate frequency
  59 { Resonz.ar(WhiteNoise.ar(0.5), XLine.kr(1000,8000,10), 0.05) }.play
  60
  61 // modulate bandwidth
  62 { Resonz.ar(WhiteNoise.ar(0.5), 2000, XLine.kr(1, 0.001, 8)) }.play
  63
  64 // modulate bandwidth opposite direction
  65 { Resonz.ar(WhiteNoise.ar(0.5), 2000, XLine.kr(0.001, 1, 8)) }.play
  66
  67 ::
  68