90 lines
1.4 KiB
Text
90 lines
1.4 KiB
Text
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class:: SOS
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summary:: Second order filter section (biquad).
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related:: Classes/FOS
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categories:: UGens>Filters>Linear
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Description::
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A standard second order filter section. Filter coefficients are given
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directly rather than calculated for you. Formula is equivalent to:
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code::
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out(i) = (a0 * in(i)) + (a1 * in(i-1)) + (a2 * in(i-2)) + (b1 * out(i-1)) + (b2 * out(i-2))
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::
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classmethods::
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method::ar, kr
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argument::in
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signal input
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argument::a0
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See formula above.
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argument::a1
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See formula above.
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argument::a2
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See formula above.
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argument::b1
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See formula above.
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argument::b2
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See formula above.
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argument::mul
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argument::add
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Examples::
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code::
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// example: same as TwoPole
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(
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{
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var rho, theta, b1, b2;
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theta = MouseX.kr(0.2pi, pi);
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rho = MouseY.kr(0.6, 0.99);
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b1 = 2.0 * rho * cos(theta);
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b2 = rho.squared.neg;
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SOS.ar(LFSaw.ar(200, 0, 0.1), 1.0, 0.0, 0.0, b1, b2)
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}.play
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)
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(
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{
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var rho, theta, b1, b2;
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theta = MouseX.kr(0.2pi, pi);
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rho = MouseY.kr(0.6, 0.99);
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b1 = 2.0 * rho * cos(theta);
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b2 = rho.squared.neg;
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SOS.ar(WhiteNoise.ar(0.1 ! 2), 1.0, 0.0, 0.0, b1, b2)
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}.play
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)
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// example with SOS.kr kr as modulator
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(
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{
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var rho, theta, b1, b2, vib;
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theta = MouseX.kr(0.2pi, pi);
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rho = MouseY.kr(0.6, 0.99);
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b1 = 2.0 * rho * cos(theta);
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b2 = rho.squared.neg;
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vib = SOS.kr(LFSaw.kr(3.16), 1.0, 0.0, 0.0, b1, b2);
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SinOsc.ar( vib * 200 + 600) * 0.2
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}.play
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)
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::
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