The dynamics and physics of the Swamp are different. Sound resonates off the aluminum walls, and the field is actually underground some, so the sound gets trapped, it's ear-splitting. Much of the Neyland sound goes up and out of the stadium. I've heard it plenty loud, but not as loud as Florida or Auburn, and on par with Bama and Georgia.
Have you been there?
Definitely not the same as entering Neyland.
I don't know why more people don't stay up there. It's only about 20 miles north and it's got decent hotel, food and shopping options. And it's right on the interstate and 441, so you can get anywhere from there.