Watch the Phase Before OD online guitar lesson by Jeff McErlain from Guitar Effects Survival Guide
If you want to channel the early Van Halen guitar sound, we must put a phase shifter before the gain section. Here I am getting that sound with pedals but when Eddie did it he was playing through a cranked old Marshall Super Lead with all his pedals in front of it. So to faithfully recreate that sound we have to put the phase shifter in front of the overdrive. Also Eddie used a slow sweep on the pedal for the most part, when you do this the effect sounds less "effecty", I actually didn't realize he had a phase shifter on for years. I just heard it as Eddie's sound.