#1
https://www.youtube.com/watch?v=Pgq9kp4n49Q

This is a question regarding Nirvana's guitar tone when the distortion is cranked way up.
This is a video of Nirvana playing Come as You Are with a rhythm guitarist on MTV's Live and Loud. In the part where Nirvana are all "I don't have a gun" there is some chorus effect with full distortion and behind the distortion of the chords ringing there is this sick dissonance. Is it like chorus with tonnes of gain? What is the effect that produces this background effect? I can hear it in the In Bloom Chorus too it sounds like crickets at the night time. I cannot get those fucked up noises when I use tonnes of distortion and try chorus or flanger it doesn't sounds so subtle...like behind the normal chords the guitar is making weird feedback noises I can't describe it better than crickets at the night time. Is this called decay on reverb or something? I am sure many grungy alternative guitarists have achieved this kind of thing... you have to watch the video and skip to the "I don't have a gun" part with tonnes of distortion. Like if I just play the chords that's fine I can hear the notes but I cant get that fucked up feedback sound its kind of like DJ scratching a turn table? Its like a noise going on other than the harmony of the chords playing its like erggghhhhh eeeeee ringing sound. Please help thanks. I don't think its flanger because it doesn't really sound like that its like a completely different beast. completely filthy. The amp settings would really help too. Maybe the tone and level is turned way up? Something like that would help me tones!
#2
I can hear it in Tom Morello when he plays in Rage and Audioslave esp. Your time has come. Maybe its flanger slowed down a lot???
#3
There's two guitars playing, and it really just sounds like a Marshall or Mesa with an EHX Stone Phaser or something similar. There could be natural feedback seeping in.

Nirvana were minimalists so there's no way some very complex routing or effects are being used here. There may have been things added in post-production as well.