1st Order Allpass

bkshepard's icon

I'm trying to create a 1st-order allpass filter that works like "one half" of the phaseshift~ object. I built a 1st-order allpass in gen~ using one of the block diagrams stringtapper posted in another thread. This version uses the feedback and feedforward amount to control the transition point and slope, but I'd like to be able to use frequency and slope values like the phaseshift~ object does. Is there a way to do that?

Paste this code inside a gen~ object.

Max Patch
Copy patch and select New From Clipboard in Max.

Romain Soufflet's icon

Thank you for your patch. From what I understand of filters, no quality factor is available for 1st order filters. Then here is the patch for 1rst order all-pass filter frequency conversion to a1 coefficient (coming from https://thewolfsound.com/allpass-filter/).

1rst_order_all-pass_filter_f_to_a1.maxpat
text/plain 3.54 KB