The definitive thrash metal rhythm guitar tone. James Hetfield's sound on Master of Puppets is built on an ESP Explorer with EMG pickups through a Mesa/Boogie Mark IIC+ — a combination that produces a tight, aggressive, scooped-mid tone with razor-sharp pick attack and crushing low end. The Mark IIC+ is the holy grail of metal amps: its lead channel provides high-gain saturation with incredible note definition even at extreme gain levels. Hetfield's relentless downpicking technique is the engine that drives this tone.