Merging the worlds of Metallica and Van Halen, Metallica's James Hetfield uses a Marshall guitar amp on Metallica's 72 Seasons that was modded by Eddie Van Halen's amp guru José Arredondo. And he uses it throughout the upcoming album.

That's what Metallica producer Greg Fidelman revealed in the new issue of Total Guitar that was reported by Guitar World on Thursday (April 6).

"James has always had one of the legendary José Arredondo-modded Marshalls, a late-'60s/early-'70s Superlead head," Fidelman says. "When we did [Metallica's 2016 album] Hardwired… [To Self-Destruct], it wasn't working very well."

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But the producer goes on to explain, "When we started this album, I had a re-invigorated interest in this head. I was talking with Dave Friedman, who is very familiar with those old José mods, and he fixed it."

So Fidelman told Hetfield it "sounded insane," he continues, "and he got really excited about it. It ended up on every song. I think that's what you're hearing."

More About José Arredondo

Arredondo, who died in 1994, was a mysterious "amp wizard" now regarded among other influential high-gain Marshall amp modders such as Paul Rivera (Rivera Amplification) and Michael Soldano (Soldano Custom Amplification), as Guitar World recounted in 2010. Van Halen started dropping Arredondo's name in the '80s.

Still, there's been some speculation over how much Arredondo contributed to EVH's tone. In the 2010 retrospective, Keel guitarist Bryan Jay remembered being taken to a garage containing some of Arredondo's projects where he spotted Marshalls labeled with name tags of prominent shredders such as Yngwie Malmsteen, Jake E. Lee and George Lynch.

More About James Hetfield's Gear

Coincidentally, Hetfield has written a whole new book about his instruments that documents his personal guitar collection through writings and photographs. Messengers: The Guitars of James Hetfield is out Oct. 17 and is available for pre-order.

The coffee table book comes in a standard hardcover or two limited editions — a deluxe boxed version and one housed in a signed slipcase. Accompanied by images from photographer Scott Williamson, it gives readers 400 pages of Metallica guitar goodness.

Meanwhile, Metallica's "M72 World Tour" gets going this month. Get Metallica concert tickets here. 72 Seasons comes out on April 14. Pre-order it here.

See some samples of Messengers below.

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Messengers James Hetfield Metallica Guitar Book, Artwork + Samples

James Hetfield 'Messengers' book art
James Hetfield Messengers book
James Hetfield Messengers book
James Hetfield Messengers book

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