You hear what you see: Noises created using only a mixer and an old flanger pedal. Plus some patch cable to create feedback loops. (Okay, I added a little overall reverb and some mastering/loudness maximizing.) You need a crappy mixer to do this, otherwise there won't be enough noise and distortion to amplify in a feedback loop.

This experiment additionally uses a steep high pass filter right after the mixer in order not to kill any gear with inaudible sub-bass – a measure I introduced after almost killing an 800W PA subwoofer with this thing. When trying something like this at home, a compressor/limiter might be useful to save your ears and speakers from damage created by spontaneous outbursts from your tortured mixer.