Metallica's self-titled "Black" album was a game changer in many ways, including with guitarist Kirk Hammett who reveals that one of the songs on the album forever changed his approach to creating guitar solos.

Reflecting on the historic album with Total Guitar, Hammett cited a moment while recording "The Unforgiven" that would give him the confidence to try a new musical approach in the coming years.

Hammett recalled finding the solo for "The Unforgiven" initially being a challenge. “It wasn’t happening and then Bob Rock accused me of not doing my homework. I don’t know what he was talking about, because I arrived into the studio with all these ideas, but they just didn’t work! I had to throw them all out," recalls the guitarist.

"I was bare naked with no idea what to do,” he continued. “Bob told me he would try to tweak the sound for me and when he did that it really helped. They said, ‘Just play!’ and I was like, ‘Arrrgh! I had maybe a minute to put myself into a real mood. I just needed to block everything out and go deep emotionally. We hit record and I didn’t know what the fuck to play but something was going to come out... Something always does."

He recalls, “That solo was raw emotion. I had no idea what to do; it all came to me as I played – real improvisation. I was so happy after that, really excited and inspired.”

Metallica, "The Unforgiven"

That experience and the feeling afterward stuck with him, as the guitarist states, “I knew I needed to do more of it, and ever since that moment, I’ve worked on being better at improvisation and completing music thoughts that are very much listenable. Forming complete solos naturally, if you know what I mean."

“For the 'Black' album, I came in with 80 percent of the stuff worked out and 20 percent was improvised, including 'The Unforgiven' solo. Nowadays I prefer to have it the opposite way, with 20 percent worked out and 80 percent improvised, because it’s more exciting, more spontaneous and honest," Kirk adds.

“I don’t know what’s going to be on the album as much as anyone else! It feels right doing it like that, it feels better – rather than composing something and making it fit, sometimes forcing things where they might not feel right. Pure improvisation is more real and human,” concludes Hammett.

The guitarist's work on the song obviously connected with listeners. "The Unforgiven" hit No. 10 on the Billboard Mainstream Rock Chart, crossed over to hit No. 35 on the Billboard Hot 100 and has gone on to be a gold-certified single for the band.

Metallica are currently celebrating the 30th anniversary of their self-titled "Black" album, issuing a deluxe remastered box set as well as pulling together artists from across a variety of genres to cover songs from that album for their Metallica Blacklist release.

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