Rob Trujillo Names Biggest Differences Between Playing in Metallica and Infectious Grooves

According to Metallica bassist Robert Trujillo, there are some significant differences when it comes to playing in his main band and supergroup Infectious Grooves.

A somewhat of a surprise for a Metallica member to be doing something on the side, Trujillo has teamed up once again with Infectious Grooves for the first new music in over two decades. Fronted by Suicidal Tendencies vocalist Mike Muir, the band’s new recordings will also feature former Slipknot drummer Jay Weinberg.

But after some long-awaited work in the studio, everybody wants to know what it’s like to be making this music again. In a recent chat with Wall of Sound, Robert discussed the differences between Metallica and Infectious Grooves from his perspective.

Robert Trujillo // Wall Of Sound Interview 2024

“As a bass player, it’s a different challenge for me,” he explained. Obviously, despite both being metal bands, we’re still looking at two very different beasts. He added (transcribed by Killer Guitar Rigs):

“Metallica is certainly challenging, and there’s a physical thing that goes with that. And with the bass playing in Infectious Grooves, I feel like I’m using different muscles, different techniques.”

“The style is a bit different, the feel,” Rob added. “It’s a challenge in a lot of ways, but [it] kind of opens my eyes to being a musician in what, ‘Wow, I used to do this!’ It’s fun to reconnect, but it is a challenge.”

In order to prepare himself for this other band, Trujillo admits that it took some practicing and doing stuff differently just so he could get used to it:

“I’ve been doing certain types of scales every night before I go to sleep and just trying to get my stamina up for that style of playing because it’s different, and it’s aggressive in a different way. But it’s a lot of fun, and I’m looking forward to it. I feel like I’ve been playing more than ever lately.”

During the interview, Trujillo also reflected on way back in the day when Infectious Grooves were doing some of their first shows. The band was formed in 1989 and Rob has been a constant member. However, as it turned out, from the very beginning, the band showed success at the local Hollywood scene, attracting enough audience to sell out entire venues. He recalled:

“Back then, we’d play a local show in Hollywood, and it’d be like, ‘Is anyone going to show up?’ And then we’d find out that that gig would sell out, which was cool.”

“And then the next step up from there, same thing — ‘Is anyone gonna even come to the gig tonight?’ because it was different back then. You didn’t have the internet, promoting gigs was very street, a lot of it you had to do on your own, or you had to put your own ads out. It was very independent back then. So we never really knew what the gig was going to become.”

Infectious Grooves Live in San Francisco 1991 - Full Show

Despite their pessimism, the newly formed band was surprised by the response in the scene at the time and, as it turns out, a lot of people were lining up to attend the show. He continued:

“And then — I think it was the second gig — we played at a venue called The Palace in Hollywood, and that gig maybe holds 1800 or 2000, at best, but there was a line around the block. And everybody came to that show.”

“I mean, it was like Social Distortion, Rage Against the Machine, the guys from Slayer, the Chili Peppers were on stage, Fishbone was there, all these actors. All of a sudden, the band had this interesting cast of characters checking us out.”

Infectious Grooves - Infectious Grooves

“Some of the guys in our band knew some of these people, but there were different factions attached to each member. Our guitar player was friends with David Arquette — he was his roommate, and he was a famous actor back then — so David Arquette brought all these people, and Keanu Reeves is there and River Phoenix and blah, blah, blah.”

“Then you got the Chilis there, and they got their gang, and you got the Fishbone guys and their gang, Social Distortion, and that’s just to name a few. So we’re just kind of like, ‘Wow, this is really happening.'”

“And for us, we didn’t know all these people, so it was a lot of pressure. But that’s how it’s been — there’s been these magic moments and these surreal moments. And I guess the beauty in it is [that] it’s never certain.”

Jay Weinberg - Infectious Grooves "Frustrated Again" Practice Drum Cam

Photo: Carlos Rodríguez/Andes (Robert Trujillo 29.10.2016)

  • 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.