Eli5: What’s the mechanism by which a multitude of voices become LOUDER and can be heard farther, than a lone voice at the same source?

Question

I live close enough to a sports stadium to occasionally hear the roar of the crowd. But that’s just a bunch of individuals all yelling and making various noises. If that were single individual in the same stadium, I wouldn’t be able to hear anything. Do our voices amplify each other somehow, when in a group?

In: 13

Answer 1

Ever play the parachute game as a kid? One person shaking a parachute doesn’t do very much. If you put a ball on it, it’s not going to do anything too crazy. If everybody starts shaking the parachute together, you can get some huge motions. Even if everybody starts shaking it in their own way, the combined wiggles can make the ball leap off and hit the roof.

Sound is like these wobbles but in the air. The stadium is like everybody shaking the parachute at the same time but in their own way. It all adds up!