#N canvas 269 0 593 306 12; #X obj 113 68 biquad~ 0.83774 -0.06338 0.06338 -0.83774 1; #X obj 113 42 biquad~ 1.94632 -0.94657 0.94657 -1.94632 1; #X obj 94 125 biquad~ -0.02569 0.260502 -0.260502 0.02569 1; #X obj 94 151 biquad~ 1.8685 -0.870686 0.870686 -1.8685 1; #X obj 94 15 inlet~; #X obj 113 97 outlet~; #X obj 94 178 outlet~; #X text 32 210 This is a pair of 4th-order all-pass filters whose outputs somehow manage to be about 90 degrees out of phase from each other. Both have different phases from the original. Adapted from a 4X patch by Emmanuel Favreau \, circa 1982; #X connect 0 0 5 0; #X connect 1 0 0 0; #X connect 2 0 3 0; #X connect 3 0 6 0; #X connect 4 0 1 0; #X connect 4 0 2 0;