On the vocals. It starts at about 2 minutes. I'v heard tucker use it on morbid angel albums as well.
[VIDEO]http://www.youtube.com/watch?v=UOlRlDGkHR4]Nader Sadek - Awakening/Petrophilia - YouTube[/VIDEO]
Hmmm... I'm not sure. Maybe a phaser with a fast rate, and some other filter? Hopefully someone with more knowledge chimes in because I am curious as well.