It's well known that Metallica have a meticulous process for constructing songs, but where does one even begin when Kirk Hammett submits 700 riffs for what would become 72 Seasons?

It's a staggering amount of musical ideas to sift through, but this type of volume is nothing new for Hammett. Prior to the release of 2016's Hardwired... To Self-Destruct, the guitarist lost his iPhone which contained about 250 ideas and, as early as 2017, he admitted he had another 500 or so ready to go for new material. Clearly, that creative flame continued to burn as he built up a riff library of even more idea, leaving producer Greg Fidelman and drummer Lars Ulrich with quite a lot of work in the early stage of the 72 Seasons writing process.

Fidelman elaborated on the making of the record and the challenges of the remote sessions amid the pandemic in the latest So What! interview for Metallica's website.

Describing the daunting process, Fidelman explains, "I started going through riffs, helping Lars go through the ridiculous amount of ideas. It was hard to even begin sifting through them. So me and Lars would listen to riffs together, and we’d categorize them really quickly. It’s a fast riff, it’s a slow riff, it’s a 'picking patterns,' it’s metal. And then give it a grade."

At first, the two assessed a pile of 300 ideas, then shifted gears and went through material that was recorded either at HQ or during tour rehearsals. "Then after that, Kirk sent me, I don’t know, 700 things…," Fidelman notes.

The producers says Hammett even acknowledged he needed help sifting through it all.

Fidelman continues, "So when I told Lars how many Kirk had, Lars was like, 'I’m not trying to get out of this, but why don’t you go through and knock it down halfway? Just the things you think are promising… split it in half at least. It’ll take us a month to go through that together.' So I did that. Then once me and Lars had our pile of A-list riffs, I guess I’d call it, we’d pick 10 or 12 for a day."

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Metallica notoriously experiment with variations of riffs and drum beats to back them in an attempt to identify the ideal version of each idea before stitching them together to make a song. This already laborious process could not have been easy with what Fidelman has revealed to be over 1,000 ideas that were in the mix overall.

Read the full interview, where Fidelman elaborates on the more collaborative nature of 72 Seasons, right here.

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