Linkin Park are just a few weeks away from the 20th anniversary of their debut album Hybrid Theory.

Now, Mike Shinoda, Brad Delson, Dave Farrell and Joe Hahn are reflecting back on their early recording days and hearing Chester Bennington sing for the first time.

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In celebration of the Hybrid Theory anniversary, Linkin Park are releasing a super deluxe box set of the album. Among numerous other rarities, Linkin Park are releasing 12 unheard demos including "Pictureboard." The demo is considered one of Linkin Park's "holy grail" recordings and has only been played live in concert once.

"Pictureboard" was written when Linkin Park were still called Xero and a version of it was eventually passed onto Bennington in 1999. According to Louder, the demo was given to Bennington by an acquaintance in the music business who knew Xero were looking for a lead vocalist.

Bennington went on to record vocals for the demo and the track eventually made its way back to the band. As Delson shares, "Pictureboard" is the first recording Linkin Park heard Bennington's vocals on. The band were so impressed with Bennington's performance that they instantly knew they had to meet him.

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“I think 'Pictureboard' was the first thing I heard Chester’s voice on,” he recalls. “I remember getting that, and being like, ‘Hey, what do you think of this guy? He just sent us this recording…’ and being like, not crying with joy, but like almost crying, just like, Wow! I don’t even know what that is. He‘s tiny and vulnerable on the verse and you could hear all these timbres and harmonics, like overtones, in his voice on the heavy part. It just blew my hat off my head, and we’re like, ‘We gotta meet this guy!’”

Back in 2016, Bennington told Metal Hammer that he knew "Pictureboard" was special as soon as he heard it.

“The second I played the demo, I knew it was special,” Bennington said. “I knew right away. I thought, ‘This is the one.’”

During the band's recent press conference, Shinoda was asked about Linkin Park's first rehearsals with Bennington. For Shinoda, he says that both he and his friends were instantly awestruck by the singer's talent.

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“We were so protective of like, the identity of the band, and what we were trying to do,” Shinoda says. “We had this vision of what it was supposed to be coming into focus, and it wasn’t there yet, but we really wanted to get it right. And so when Chester came in, I remember we all couldn’t stop talking about how talented he was and what a voice he had."

Before joining Linkin Park, Bennington was the frontman of rock group Grey Daze. It was during Linkin Park's early recording days, however, that Bennington began to discover who he wanted to be as a vocalist.

“When we were making demos together and doing stuff for the first time," Shinoda continues. "He was still discovering who he wanted to be as a vocalist as well. It was partially like, how he could express himself in a unique way, but then also what would fit this style of music, what would fit this band the best."

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Back in August, Linkin Park unveiled their unreleased demo "She Couldn't." In 2009, the track first surfaced when a fan discovered a demo CD on eBay. Since then, it has made its way onto YouTube through various fan uploads over the years.

Shinoda shares that "She Couldn't" was particularly important for the band as it helped them find their identity early on in their career.

"Looking back at that one," Shinoda says. "I don’t know if I realized it in the moment, but 'She Couldn’t,' to me, was so cool because it had… For example, lyrically, it had the line ‘You’re not alone,' he didn’t scream in the song, there were no heavy, distorted electric guitars in the song.

The entire rhythm track was mostly sampled. And in one song, like super super early on in our relationship together with Chester, it was like this was the type of song that would become part of our identity way down the line. Like it was pointing the compass in the direction of 2010, or 2007. It was all in there, we just had to discover it.”

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Earlier this month, Hybrid Theory was certified 12x platinum in the United States. This feat means that the album has now sold more than 12 million copies since its release in 2000.

Various songs from Hybrid Theory have also earned their own certifications. “In The End” is 4x platinum-certified while “One Step Closer” is platinum-certified. As well, “Papercut” and “Crawling” have both earned gold certifications over the years.

Hybrid Theory: 20th Anniversary Edition arrives on Oct. 9 via Warner Records as a super deluxe box set, super deluxe vinyl set, deluxe CD and digital version. Head here to pre-order and/or pre-save the forthcoming release.

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The super deluxe box set includes five CDs: Hybrid TheoryReanimationB-Side RaritiesLPU Rarities and Forgotten Demos. The aforementioned box set and a super vinyl deluxe set will also feature three LPs, which will include Hybrid TheoryReanimation and Hybrid Theory EP.

More information on the new anniversary box set is available here.

Watch Mike Shinoda unbox the Hybrid Theory: 20th Anniversary Edition below.

What is your favorite song on Hybrid Theory? Let us know in the comments below.