Do you mean this version?
http://www.youtube.com/watch?v=qFtVmAa9d4U
It sounds fairly straight forward to me, mid range growl I would call it. Just a nice rig with the mid high and mid lows slightly more dialed up and the bass and highs slightly dialed down. It's a good sound that cuts through the mix, however he got the tone I think it's good. Perhaps it's a GK amp.
I'm not an expert on this sort of thing, so there may be plenty of better explanations.