hilbert~.pd

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#X text 34 232 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;
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#X text 461 13 bang to clear;
#X text 80 16 signal in;
#X msg 502 112 clear;
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