No, it’s not a fan. That, ladies and gentlemen, is the world’s most powerful subwoofer: the Eminent Tech TRW 17.
It reminded me of my experiments when I was in high school. I've read about infra-sound (extremely low frequency sound) and its harmfull impact on human beings. So, I was attaching a balloon to little electrical rotor engine. Depending on the pressure in the balloon and it would rotate at different speeds producing some low frequency waves. It was FUN!