Here’s a patch I made that performs frequency domain filtering. It’s a time varying filter with random modulation of the position, number and spacing of multiple peaks. The patch works in both Purr Data and Pure Data Vanilla (at least in Windows). The patch seems to immediately crash Vanilla on macOS, but it works fine in Purr Data. I don’t know if I can fix this. You can ignore any “expr divide by zero detected” messages.

Here’s the original recording where I used this: