Kirk Hammett’s Tech Names Biggest Advantages of Metallica Going Digital, Discusses How They Make Guitars Work in the Mix

According to Kirk Hammett’s tech, Justin Crew, there are a few important advantages of going digital for live shows. Justin addressed this during the chat with Doug Doppler Music, explaining how they’ve “embraced technology” and how “it’s been good to us.”

Justin’s been with Metallica since around 1996 and has seen Kirk Hammett’s and James Hetfield’s rigs evolve a lot over the years. Asked about the matter, the tech replied (transcript via Ultimate Guitar):

“When I started, we were [running] TriAxis, a clean and lead with rack-mounted rectifier heads, with a Bradshaw pedalboard. There was a Whammy pedal in the middle of it somewhere… Strategy 400 powering the iso [isolation] cabinets; powering the speakers on stage…”

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“Slowly went to the Randall Egnater with the plugin modules. Then, the Fortin Meathead modified for Kirk — solid amp, never let me down.”

All of this changed in 2013 when Metallica decided to be the first band ever to play all seven continents, creating a now-legendary concert release called “Freeze ‘Em All.” But in order to pull it off, James, Kirk, and the band’s crew couldn’t just use tube-driven amps without potential issues with the tone consistency or the general safety of these amps and their accompanying cabinets and microphones.

“When we went to Antarctica, everything had to be solar-powered,” Justin recalled. “We wound up with the Fractal.”

“With the Fractals, it’s identical across the board. We’re not micking up speakers that are wet because it’s humid; it’s all very, very consistent. When they’re in the tuning room, they’ll plays some of the songs that we’re going to play that show.”

Metallica - Freeze 'Em All: Live in Antarctica (FULL CONCERT) [HD]

Explaining further that they can “do things with the Fractal that we can’t do with a real amp,” Justin added that “the noise floor is so much lower” as well.

But getting great tone with modelers isn’t at all simple. What may sound great on its own can turn out to be pretty odd in the full mix. Justin confirmed that they had to give up on some of the tones that they made because they weren’t really working in the mix. He explained:

“When we first started, because we were using iso cabs in the tube amp world, we found that that warmth, where the cabinet kind of struggles to breathe because it’s pushing against these four walls…”

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And that’s exactly the aspect that was really difficult to emulate using Fractal:

“It took us a long time to emulate that in the Fractal. And then we sat James down with it, all pleased about ourselves because it took us two days to get back together, and James went, ‘Yeah, but still got that annoying thing about it with the iso cabinet.”

Justin had to sit down with James’ tech, Chad Zaemisch, and figure this out. And finally, they had their “eureka moment”:

“At that point, I think both Chad [Zaemisch] and myself realized, ‘Oh, we we’re not necessarily going after the same. We’re going after better!’ That was literally a eureka moment for both of us. We realized we got to stop thinking like it has to be the same as what they had because we can do better.”

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“And yes, once you get the whole band going, then it can maybe not fit. We recently tried approximating the sound of ’72 Seasons’ and we went more in that direction with Kirk. But then, once Greg FIdelman [producer] had heard the recording, he was like, ‘Ah, sounds great on its own, [but] it just doesn’t sit in the mix, right. Can you go back?’ So we did. And now everything’s happy.”

James’ tech, Chad Zaemisch, also recently discussed Metallica’s decision to use Fractal Audio Axe-Fx modelers as opposed to other options on the market. According to Chad, there was one particular feature that really made the difference for them:

“Back when we were going to make a run at the digital realm, the Axe-Fx was really the only one that could have two amps at the same time going because that’s what we were doing with our analog gear — we had the Mesa Boogie sound, and the Diesel sound.”

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“In order to have them stay synched exactly up the whole time, you’d have to have them in the same unit, and the Fractal does a really great job of time-aligning everything before it comes out as well. You can even kind of fudge things around a little bit, but that phase between those two amps is so unbelievably important.”

“I mean, you can move a couple of milliseconds on one waveform or the other, and it just completely changes the sound. And it had two different main outputs — it has four, of course, but it’s got two of the main XLR outputs.”

Photo: Raph_PH (Metallica – The O2 – Sunday 22nd October 2017 MetallicaO2221017-94 (37897469751)

  • David Slavkovic

    David always planned for music to be nothing more than a hobby. However, after a short career as an agricultural engineer he ended up news editor at KillerGuitarRigs, senior editor at, as well as a freelance contributor to online magazines such as GuitaristNextdoor and brands like Sam Ash.