#N canvas 759 122 578 569 12;
#X obj 33 18 biquad~;
#X obj 161 334 env~;
#X floatatom 161 365 6 0 0 0 - - - 0;
#X floatatom 62 203 5 0 0 0 - - - 0;
#X obj 62 334 env~;
#X floatatom 62 365 6 0 0 0 - - - 0;
#X text 87 395 Compare the value of the straight signal on the left
with the value of the filtered signal on the right.;
#X obj 161 304 biquad~ 1.41407 -0.9998 1 -1.41421 1;
#X msg 161 200 1.41407 -0.9998 1 -1.41421 1;
#X text 47 88 y(n) = ff1 * w(n) + ff2 * w(n-1) + ff3 * w(n-2);
#X text 47 105 w(n) = x(n) + fb1 * w(n-1) + fb2 * w(n-2);
#X msg 195 266 clear;
#X obj 62 249 osc~ 5512.5;
#X text 236 330 this biquad~ is a notch filter for;
#X text 232 347 fn = Pi/4 (= SR/8 = 5512.5Hz @44.1k);
#X msg 450 181 \; pd dsp \$1;
#X obj 450 156 tgl 15 0 empty empty empty 17 7 0 10 #fcfcfc #000000
#000000 0 1;
#X text 473 155 DSP on/off;
#X text 95 17 - a 2nd order (2-pole / 2-zero) filter;
#X text 46 65 Biquad~ calculates the following difference equation:
;
#X text 349 495 updated for Pd version 0.30.;
#X text 57 462 see also:;
#X obj 188 487 rzero~;
#X obj 131 510 cpole~;
#X obj 131 487 rpole~;
#X obj 245 487 rzero_rev~;
#X obj 188 510 czero~;
#X obj 245 510 czero_rev~;
#X obj 131 537 lop~;
#X obj 172 537 hip~;
#X obj 214 537 bp~;
#X obj 251 537 vcf~;
#X obj 296 537 bob~;
#X text 23 498 raw filters =>;
#X text 337 537 <= user-friendly filters;
#X obj 131 462 fexpr~;
#X obj 186 462 slop~, f 7;
#X text 45 132 The filter's coefficients syntax (set via arguments
or list input) is: fb1 fb2 ff1 ff2 ff3, f 54;
#X text 268 227 set internal state (previous input samples), f 24
;
#X msg 180 235 set 0.5 0.4;
#X text 243 266 or clear memory (same as 'set 0 0').;
#X text 158 178 list sets filter's parameters;
#X connect 1 0 2 0;
#X connect 3 0 12 0;
#X connect 4 0 5 0;
#X connect 7 0 1 0;
#X connect 8 0 7 0;
#X connect 11 0 7 0;
#X connect 12 0 4 0;
#X connect 12 0 7 0;
#X connect 16 0 15 0;
#X connect 39 0 7 0;
