ZDF Combs and AllPass Filters
building blocks for ZDF reverbs and delay-based FX
comb and all-pass filters was taken out form the book 'Physical Audio Signal Processing' by Julius O Smith III.
download file includes an
-Feedback Comb Filter,
-Filtered-Feedback Comb Filter,
-Feedforward Comb Filter,
-and one of Schroeder's early reverberator modules that shown in the screenshot. ('early reverberator' as 1960s early NOT to be confused with 'early-reverb', the 'early-reverb' part is made out of tap-delay line. this JCRev is more of an 'late reverb' part of a reverb effect.)
I hope you guys and girls will find it usefull.
enjoy and stay safe.!