ref: 2ac9bbe152f450558964858cff656592eacebbae
parent: d6e60b6287518204641c38164de6776c58ec7bcb
author: Olav Sørensen <olav.sorensen@live.no>
date: Wed Dec 21 07:19:44 EST 2022
Add source of LED filter code in comment
--- a/src/pt2_ledfilter.c
+++ b/src/pt2_ledfilter.c
@@ -1,4 +1,6 @@
-// Crude Amiga "LED" filter implementation
+/* Biquad low-pass filter with resonance, from:
+** https://www.musicdsp.org/en/latest/Filters/38-lp-and-hp-filter.html
+*/
#include "pt2_ledfilter.h"
#include "pt2_math.h"