Martin Golub modded plexi. Amp has the SE Lead mod done and a Metro Zero Loss fx loop added. Same mod and modder used by Doug Aldrich, Reb Beach and countless others. Very aggressive, pissed off Marshall tone. iPhone clip really does it no justice.
http://youtu.be/5nQvI5Qgi1o
Guitar is a Les Paul with a JB in the bridge. Guitar straight in, gain at about 4 on the dial. Master volume around 2.