One of our roosters is in solitary right now after being torn up by the other one and we brought him into the house last night to keep him warm. He was pretty pathetic and hadn't made a sound all day - not his usual style. But at 6:10 this morning he woke us right up. Since he's usually a lot farther away, it really got our attention, I happen to have a decibel meter so I got it out and set it to show the maximum level it "heard". I put the meter about 4 feet from the rooster and after an hour it showed a reading of 98.5 decibels dba. Here are some other noise decibel levels to compare: http://www.gcaudio.com/resources/howtos/loudness.html. According to that, this rooster was louder than a jackhammer at 50' or a subway train at 200'. Of course it was only 4 feet away but he only crowed about 3 times during that hour and he's injured - I think he can be louder. Someday I'll check it when he's healthy and back with the flock. Whatever the decibel level is, we hear him easily in our bedroom with the windows closed, 150' away and on the other side of the house. Just a little pseudo-scientific information to use in your next discussion about barnyard noises.