Pretty interesting Instagram comments from Ben:
We’re actually not using any stereo enhancing blocks on the main heavy sound, but one amp is dialed hard left and the other heard right, so the slight differences in amp feel give it that wide spread.
I’m pretty sure the phase is aligned. It’s just the magic of using two amps. Even though they are high gain amps, they are not cranked super hard so that gives the amps a tiny amount of dynamics separation also, but it’s more about the timbre differences of the amps.
Lo-Fi Filter: Use a filter block and dial in some high pass and low pass to taste. Added bonus: if you're doing things in stereo, throw a volume block at the end to make things mono, either by taking one side and putting it up the middle, or summing L and R. Use scenes to turn on and off the filter and volume block to go from big to small. You may also want to make the "LoFi" stuff about 3dB lower.
As for the amp EQ, it's honestly more about finding the right cab and then dialing the EQ around it to taste. I can’t remember what our cab/mic combos are right now.