Alongside their status as worldwide metal legends, Black Sabbath are one of the biggest British rock bands of all time, so it only makes sense that the U.K. music mag Mojo is rolling out the red carpet for the group's new '13' album with an issue providing an in-depth look at the sessions -- including a lengthy interview with producer Rick Rubin.

Rubin, who's helmed bestselling (and Grammy-winning) albums by a long list of big-name artists, admitted to Mojo that producing Sabbath's reunion record "was really like a childhood dream." Wish-fulfillment aside, however, it was not a project without its share of challenges -- foremost among them the fact that, as he put it, "They really hadn't worked together in such a long time and, because they've had such success in their career over the years, it was almost a case of red light fever. There was an anticipatory anxiety among different members of the band and they were worrying about whether [the music] would be any good, and whether they were up to the task."

Of course, even once things got started, the band hit a few bumps in the road, including the controversial departure of drummer Bill Ward. "I would love Bill to have been involved and that was always the intention," Rubin insisted. "When he decided not to be it really took everyone by surprise. It was a case of 'What do you want to do? We have all these songs but what's the process going forward?' The band said that they wanted to continue. Then it was a question of trying to find a drummer who could allow them to continue to do it."

To that end, Rubin put together a list of potential replacements that included at least one surprising name: former Cream and Blind Faith drummer Ginger Baker. Although Baker might not seem like the most natural fit for Sabbath, Rubin justified his nomination by explaining, "He was on my list because I wanted to get someone who had grown up in the same world as them and who jammed the way they did and there aren't many of those people left. Most of them are dead. But I was asking: who grew up listening to the same music as them? Who played in bands where they jammed back then? It's a very different thing from the way hard rock and heavy metal drummers play today. That's the kind of drummer I was looking for."

Once the band decided on Rage Against the Machine and Audioslave's Brad Wilk, the truly hard work -- of crafting new songs they felt would stand up against their legacy -- began. And while it took some major effort to bring it all together, Rubin says the end result "feels like pure Black Sabbath." As he promised fans toward the end of his interview, "It scratches that Black Sabbath itch and it evokes the same feelings as those other [early] albums. I can't wait for you to hear it."

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