I blow long drawn out screams. Usually about the same length in a series as I make for coyotes. If I can't see the bear than I try to make the screams somewhat die and not not blow to often. Enough to keep him interested and coming but not blasting the sound in his face (If he's up close). I'm not saying that by blowing loud you will discourage a bear, I've had the exact oppostite happen. But I think overall, slightly dieing down on the sound will work better. Hope this helps.