I believe it's some sort of chorus effect though a lot of it is the harmonized guitar in the backing track.

did you know the major scale on a piano, starting at whatever note (lets say E). you just go straight up the white keys without hitting a black one. and you got the major scale.


Click gear on the bottom right corner of the page. He uses a Line 6 PodXT Live so your best bet is to get one of those and tweak it.
Quote by John Mayer
"'What do you do when you've seen the most stupendous, stunning, earth-shattering show of all time?' Uh...I dunno...stop using hyperbole?"

UG 83