KILLEEN, Texas — If you watched 'America's Got Talent' Tuesday night, odds are you were captivated by Joseph Allen's charisma and beautiful voice. Even if you weren't, the judges were: Howie Mandel awarded him the golden buzzer for his performance.

The video of Joseph's audition already has more than eight million views on YouTube just 24-hours after it aired. Plus, the 21-year-old from Killeen gained about 30,000 Instagram followers overnight.

RELATED: Third time's the charm: Killeen man gets golden buzzer on 'America's Got Talent'

Before all the hype, he was just a Killeen Independent School District elementary schooler discovering his love for his craft.

"As a young kid, he had a very unique low voice," said Joseph's elementary school music teacher Travis Branam.

Surprisingly, Branam didn't put Joseph in the choir right away. 

"He was this super charismatic and gifted kid," he said. "So I felt very conflicted about not having him be in the choir at the very beginning."

He eventually gave Joseph a shot and even gave him a solo. The solo sparked his love of music, which lasted much longer than elementary school.

The two have kept in touch, and Branam got to witness Joseph's magic moment in person. 

"That was wild when he, when Howie, got up on the table to step on it, that was just, that was outrageous," he said. "They got to see what I feel like I saw when he was, when he was just a kid."

Katrin Roberson was Joseph's German teacher at Ellison High School for two years. She said he was always motivated and ambitious. 

"He's a go-getter," Ellison High School German teacher Katrin Roberson said. "He always was like that. If he wanted something, he got it."

Roberson said she's been familiar with his comedic personality and rap bars. 

"He actually took a German nursery rhyme and he made it into a rap song to get extra credit," she said.

Branam said Joseph has a humble swagger. You can tell he's confident and can give a great performance at any moment, but he also cares about the people around him. 

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