Twenty years ago, Slipknot released their debut self-titled album. Die-hard maggots will recall the album's intro track, "742617000027," and the creepy voice throughout it. But what was the inspiration behind the intro track and where did it actually come from?

As it turns out, the sample is actually taken from a documentary surrounding the Manson Family murders.

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Previously, Slipknot drummer Joey Jordison claimed the voice in the intro track was actually a manipulated version of Corey Taylor's voice.

According to Kerrang!, the origin of the sample is actually a 1973 documentary called Manson which centers around the family's killings.

The voice in the intro track says, "The whole thing, I think it’s sick" in various speeds an pitches. The voice actually belongs to Corey Hurst, a former cellmate of Charles Manson's "family member" Susan Atkins.

During their time in a shared cell, Atkins boasted about her participation in eight homicides. Hurst participated in an on-camera interview for the documentary, where the infamous line makes its debut.

Like they, they think it’s right to murder,” Hurst says. “They want to murder. Look at all the people — and they get a kick out of it, a sexual kick out of it. The whole thing, I think it’s sick. I mean, I don’t know…”

You can listen to Slipknot's intro track and the Manson documentary clip below!

We Are Not Your Kind drops Friday, Aug. 9 via Roadrunner records, with preorders available here.

Slipknot continue their Knotfest Roadshow tomorrow in Denver, CO. Tickets are on sale now with a full list of tour dates below.

08/08 – Lincoln, NE @ Pinnacle Bank Arena
08/10 – Des Moines, IA @ Iowa State Fairgrounds*
08/11 – Tinley Park, IL @ Hollywood Casino Amphitheatre
08/12 – Clarkston, MI @ DTE Energy Music Theatre
08/14 – Virginia Beach, VA @ Veterans United Home Loans Amphitheater
08/16 – Noblesville, IN @ Ruoff Home Mortgage Music Center
08/17 – Bonner Springs, KS @ Providence Medical Center Amphitheater
08/18 – Maryland Heights, MO @ Hollywood Casino Amphitheatre
08/20 – Toronto, ON @ Budweiser Stage

08/21 – Saratoga Springs, NY @ Saratoga Performing Arts Center
08/23 – Burgettstown, PA @ KeyBank Pavilion
08/24 – Scranton, PA @ The Pavilion at Montage Mountain
08/25 – Darien Center, NY @ Darien Lake Amphitheater
08/27 – Mansfield, MA @ The Xfinity Center
08/28 – Wantagh, NY @ Northwell Health at Jones Beach Theater
08/30 – Holmdel, NJ @ PNC Bank Arts Center
08/31 – Camden, NJ @ BB&T Pavilion

09/01 – Bristow, VA @ Jiffy Lube Live
09/03 – Alpharetta, GA @ Ameris Bank Amphitheatre
09/04 – Tampa, FL @ MIDFLORIDA Credit Union Amphitheatre
09/06 – Austin, TX @ Austin360 Amphitheater at Circuit of The Americas
09/07 – Dallas, TX @ Dos Equis Pavilion
09/08 – The Woodlands, TX @ The Cynthia Woods Mitchell Pavilion presented by Huntsman

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