Metallica bassist Robert Trujillo recently sat down with Rolling Stone magazine to give an update on the band's forthcoming album, as well as the film he co-produced about his bassist hero Jaco Pastorius.

As for the new album, Trujillo says, “We're working on these songs and we're having a blast. We are being productive and having fun.

When asked if the new music is sounding like their most recent effort, Death Magnetic, Trujillo said it’s too early to tell. “I can't say that yet. I really can't relate it to any album; I think every Metallica album is unique in its own way," the bassist states. “What we're doing is special and unique in its own way, but still keeping it heavy. For me as a listener, part of the journey I'm on with Metallica, there's just a certain edge that needs to be there…I can tell you that what we're doing sounds heavy, but again each album is its own little experience. So we'll just have to wait and see."

Besides working with Metallica, Trujillo has been keeping busy for the past five years as a co-producer on Jaco: A Documentary Film. The movie is a tribute to Jaco Pastorius’ jazz and rock accomplishments, as well as how influential he was to other musicians during his short life. The bassist died in 1987 at the age of 35 from a brain hemorrhage he suffered after being hit by a bouncer at a club.

Trujillo told the outlet that the documentary has been a labor of love. “It's been five years now. It's cost me a lot of money,” the bassist continued. “I know a lot of people think, 'Oh, you're a rich rock star.' We actually had to raise money to make the movie. I spent nearly $800,000 out of my pocket. I always say, 'Hey, I'm in Metallica, but I wasn't on the Black Album.'"

A screening of Jaco: A Documentary Film will be shown at the Asbury Park Music in Film Festival, taking place April 10-12. Meanwhile, Metallica are scheduled to co-headline this year’s Lollapalooza. They’ll hit the stage on Aug. 1 in Chicago’s Grant Park.

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