try this one.
go maelstrom audio mains out -> thor ins 1&2
thor outs 3 &4 - > Maesltrom Audio ins
creates a feedback loop
setup the matrix for audioin1&2>filter3ins 100%
audio in 3&4.audio 1&2 . setup up a combinator control assigned to corresponding mod destination Amount. i like to attach the pitch bend as the default is zero/no feedback. THIS will control the amount of feedback. WATCH OUT put a maximiser with soft clip enabled to avoid damage .tip!
this can be further manipulated in numerous ways

mental