Went to the Ohio State/Oregon game this year. It was the loudest game I've ever been to. RES is also super loud. But both of those places have closed-off stadiums. Autzen is even slightly built into the ground.
LES is about as open as it gets. Especially with 4 empty corners. If the stadium was closed off like those two and it had an awning like Autzen, then that place would be INSANE.
People can say that RES and Autzen are louder. They're right. But it is because they have to resort to acoustics.