FYI: "James Hetfield’s Guitars and Gear" "...Hetfield is known for using very few effects in his signal chain, and for those he does use they are usually controlled by his guitar tech behind the scenes. His sound is more result of his amp setup, and the use of an EQ. – ProCo Rat Distortion pedal Used on “Kill ’em All” in combination with a modified Marshall. – Ibanez Tube Screamer Used on “Ride the Lightning” as the replacement for the stolen ProCo Rat. This was the last time he’d use a distortion pedal in his signal chain, as he moved toward using a Mesa Boogie/Marshall combo to get most of his sound. – TC Electronic G-Major 2 Used nowadays for his effects during live performances. The unit is controlled by his tech but it allows James to get effects from older albums without going through a box full of effects. [James Hetfield Metallica Gear Run by Chad Zaemisch] – MXR Phase 100 – Digitech Whammy – Dunlop Cry Baby Wah – Line 6 DM4 – Klon Centaur – Boss NS-2 Noise Suppressor – Lovetone Brown Source ... – Black Album For the Black Album James used a modified Marshall amplifier (JCM800), his old Mesa Boogie Mark IIC+, the new Mesa Boogie Mark IV, as well as the Strategy 400 power amp and ADA MP-1 preamp. ... " ZOOM G1/G1X FOUR has "BG MK1" and "BG MK3" Mesa Boogie combo amp models and respective cabs. For JCM800, there's "MS 800" model. It may be a good starting point to try.