Made a separate topic, because it's interesting. You know those video buzz, as if from hell, but they make you think.
But I think I have an explanation. I work at a construction site, and watched these videos with rumble past. At the construction site, I heard a similar sound when given a run drill. What can - then convert the vibration of the walls, but it was similar to this one. Not as strong, but if the hammer work belong to any large pipe, you get both the video. :)
Tell me I'm wrong, or is this really the roar from the underworld. Damn a fight those demons.