During today's appearance on The Howard Stern Show on SiriusXM (April 12), Metallica chatted about a variety of things, shedding light on their songwriting processes individually and as a team, including how Kirk Hammett and Lars Ulrich teamed up to perfect the now iconic "Enter Sandman" riff.

To keep things simple (and for everyone's sanity), we'll be referring to the two halves of this mighty and memorable guitar riff as the "lick" (the first half with the lead melody) and the "tail" (the crunchy, meatier second half).

Shifting the topic of discussion away from James Hetfield's guitar playing style, Stern prompts Hammett to play the "original" idea he had for "Enter Sandman," something that feels like an impossible ask, but it's the type of feat the legendary talk radio host has a knack for pulling off.

What Did the Original Riff Sound Like?

The difference in the original riff concept and what has become Metallica's calling card and the gateway song for so many heavy metal converts, is minor on paper, but the subtlety inarguably elevates "Enter Sandman" to the household hit it is now.

Hammett plays the "lick" (see above) and "tail" in succession each time on the air, revealing it was Ulrich who instead suggested he play the "lick" three times and then follow it up with the "tail" component.

The result is what we all know and love now.

READ MORE: 10 Things We Love About Metallica's New Album, '72 Seasons'

Why Did Lars Make That Suggestion?

"There's a thing that we do with riffs where sometimes we'll structure it where there will be a repeating pattern for three times and then an answering part (a tail). And, basically, he was just morphing it into a workable form," Hammett explains (all transcriptions by Loudwire).

"Obviously we're getting way into the weeds of it, which is cool because I've never done that," Ulrich chimes in, "but you've got to go back a little bit and you've got to, at some point, you've got to remember your influences and your inspirations."

Continuing, the drummer says, "The reason we're playing music, James mentioned Tony Iommi, we're all sitting here because of all the things that we all grew up on. In my case, Deep Purple. In my case, Black Sabbath. In my case, Thin Lizzy, Iron Maiden, Judas Priest, etc. etc. Kirk has got his own arsenal of that, so does Robert [Trujillo]. So, when you say, how do you come up with that? Well, there's certain things that inspire you and you start understanding. Okay a band called Diamond Head, they had these songs and the way that they structured their riffs and they repeated — James used the word tail — they would have a melodic element to a riff and then a tail, but most of it was three and one."

Lars Explains Metallica's Musical Direction on 'The Black Album'

Ulrich then explains that Metallica's intension to simplify their songs came as a byproduct of touring behind the ...And Justice for All album, noticing they were "losing the audience" with some of their more prog-addled, stretched out tracks.

He says "Enter Sandman" was the first song from Metallica's summer of 1990 songwriting sessions and served as the "battle cry" for their new musical direction that would later take form of their self-titled 1991 album, better known as 'The Black Album.'

Viewing Hammett's riff as the foundation of a song, enhanced by the aforementioned repetition suggestion, Ulrich recalls his and Hetfield's goal being to "write one song around one riff, which we had never done before." It inspired the clean-tone guitar intro in the song, as well as other iterations of the immortal riff appearing elsewhere in the song.

"It was a direct answer to the last album, which was nine songs full of all these crazy, almost prog-like song structures," Ulrich reiterates.

Metallica in 2023

Metallica's new album, 72 Seasons, will be released on Friday (April 14) and their worldwide tour is set to kick off on April 27. See the upcoming dates here and head to this location to get your tickets.

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