A standard second order filter section. Filter coefficients are given directly rather than calculated for you. Formula is equivalent to:
out(i) = (a0 * in(i)) + (a1 * in(i-1)) + (a2 * in(i-2)) + (b1 * out(i-1)) + (b2 * out(i-2))| in |
signal input |
| a0 |
See formula above. |
| a1 |
See formula above. |
| a2 |
See formula above. |
| b1 |
See formula above. |
| b2 |
See formula above. |
| mul | |
| add |
// example: same as TwoPole({ var rho, theta, b1, b2; theta = MouseX.kr(0.2pi, pi); rho = MouseY.kr(0.6, 0.99); b1 = 2.0 * rho * cos(theta); b2 = rho.squared.neg; SOS.ar(LFSaw.ar(200, 0, 0.1), 1.0, 0.0, 0.0, b1, b2)}.play)({ var rho, theta, b1, b2; theta = MouseX.kr(0.2pi, pi); rho = MouseY.kr(0.6, 0.99); b1 = 2.0 * rho * cos(theta); b2 = rho.squared.neg; SOS.ar(WhiteNoise.ar(0.1 ! 2), 1.0, 0.0, 0.0, b1, b2)}.play)// example with SOS.kr kr as modulator({ var rho, theta, b1, b2, vib; theta = MouseX.kr(0.2pi, pi); rho = MouseY.kr(0.6, 0.99); b1 = 2.0 * rho * cos(theta); b2 = rho.squared.neg; vib = SOS.kr(LFSaw.kr(3.16), 1.0, 0.0, 0.0, b1, b2); SinOsc.ar( vib * 200 + 600) * 0.2}.play)