Trae Patton/NBC Simon Cowell
Ahead of Tuesday night's episode, Cowell spoke to PEOPLE about what fans can expect — and what he's most looking forward to, now that there's a new format for the series' live episodes.
"We had a ton of great people this year," explains Cowell, 62. "So trying to get that number down to 36 would've been really difficult. In some ways we've made it easier by putting more people through. In other ways, we've made it harder because only two people per night are going to go through to the final. But I think that's more exciting."
As revealed last week, AGT will return to the Pasadena Civic Center on Tuesday for six weeks of live shows, with the results shows to air the following night on Wednesday.
In a historic move, the judges — Cowell, Howie Mandel, Sofía Vergara and Heidi Klum — have divided 55 acts into five qualifying rounds. The acts will each get a chance to perform live, but only two of 11 — one from the viewer overnight vote and the other chosen by the judges from the acts that placed in second, third and fourth — will move directly into the finale each week.
"Not knowing what's going to happen until it happens, I think, makes it more exciting," Cowell says of the new format. "Compared to where we were a year ago, where seven people went through per night, I didn't feel there was much at stake, if I'm being honest."
Sami Drasin/NBC Simon Cowell
"I think the Wednesday shows will have a very different dynamic and energy this year," Cowell continues. "It does put more pressure on contestants, there's no question. But that was done so we could see more people this year."
"When we had to decide the 55 [acts], it really was difficult because you've got a limited amount of time to make the decision. No one can agree," he adds of narrowing down the talent. "So in the end, we were like, 'Well, let's just look at who's got the most view counts. Who do we think the public want to see the second time?' You're never going to get it a hundred percent right. But I think we pretty much got it right."
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With the stakes even higher, Cowell says he's looking forward to seeing his Golden Buzzer-winning act, 14-year-old singer Sara James, take the stage again to deliver another show-stopping performance. The Poland teen previously wowed the judges with her rendition of Billie Eilish's "Lovely."
"It's so hard, trying to put myself in her position, which is, 'Do you do something safe, or do you do something different?' My advice always is do something outside of your comfort zone, do a song no one's done a great version of, make it your version, but it's really hard," he says of his hopes for James. "I tend to think when you play it safe, it doesn't work so well for you. I think sometimes you've got to take a slight risk and do something original, but there's so much at stake."
Trae Patton/NBC From left: Howie Mandel, Heidi Klum, Terry Crews, Sofia Vergara, Simon Cowell
At the end of the fifth week of live shows, the top 10 finalists will be announced alongside an 11th "Final Wildcard" act, which will be chosen by viewers on Sept. 7. The wildcard vote will consist of four eliminated live show acts chosen by the judges.
From there, the top 11 finalists will compete one more time for America's vote during the two-night finale on Sept. 13 and 14. The winner will then be awarded the $1 million prize, as well as the chance to perform in "America's Got Talent Las Vegas LIVE" at Luxor Hotel and Casino in Las Vegas.
The first round of America's Got Talent live shows airs Tuesday at 8 p.m. ET on NBC.
See the full list of performers below...
ACTS ADVANCING TO THE LIVE SHOWS: Acapop!, Aiko Tanaka, Amanda Mammana, Amazing Veranica & Her Incredible Friends, Amoukanama, Aubrey Burchell, Ava Swiss, Avery Dixon, Bayley Graham, Ben Lapidus, Blade 2 Blade, Celia Muñoz, Chapel Heart, Cline Twins, Don McMillan, Drake Milligan, Duo Rings, Freckled Zelda, Funkanometry, Fusion Japan, Harper, Hayden Kristal, Jack Williams, Jannick Holste, JoJo and Bri, Kristen Cruz, Kristy Sellars, Lace Larrabee, Lee Collinson, Lily Meola, MPLUSPLUS, Madison "Maddie" Taylor Baez, Max Ostler, Mayyas, Merissa Beddows, Mervant Vera, Metaphysic, Mia Morris, Mike E Winfield, Mr. Pants, Nicolas RIBS, Oleksandr Yenivatov, Players Choir, Sara James, Shu Takada, Stefanny and Yeeremy, The Brown Brothers, The Lazy Generation, The Pack Drumline, Travis Japan, urbancrew (Flyers of the South), Wyn Starks, XOMG POP!, and Yu Hojin.
ACTS IN CONTENTION FOR AMERICA'S WILDCARD: Auzzy Blood, Ben Waites, Debbii Dawson and Jordan Conley.