Yelling in a quiet neighborhood.

I live in a very quiet neighborhood. It's summertime and there are lots of windows open. Every once in a while I hear a guy yell. Just: "arrrggghhhh!" I don't know where he is. Maybe he's one of those grunting weightlifter types. It's only just mildly disturbing. Or should I worry that somebody has a problem? But I don't quite know where. It just floats over the whole neighborhood.