High mids, low lows, low highs.

EDIT: Most of it comes from the natural cleans of the amp.
Live Rig:
Ibanez Rg 150R w/ Duncan 59s
Marshall JCM2000 TSL60 Head
Mark IV Combo
Marshall 1960a Cab w/ Vintage 30s
Ibanez RG1570 Prestige w/ Duncan 59s
Jackson SLSMG Soloist
Currently in Ontario, Canada.

i think metallica had a scooped sound to there cleans, at least when using the jc's?