Owls are all about silence. Their whole existence takes place in the stillness of night. Their world is quiet. Specialized feathers make their flight so completely, amazingly silent that an owl can fly right over your head and you won't know it until you feel the hairs on the back of your neck stir. Our nest box is on a tree between the sidewalk and street, in a (usually) quiet but populated downtown neighborhood with a sports field full of amplified announcers and cheering, horn-blowing spectators a block away in one direction, (making it less quiet on football weekends) and a school full of screaming children within a block in the other direction (making it less quiet during recess), and the occasional sound of cars gunning it from a stop sign for a one-block sprint to the next stop sign. Add in leaf blowers, barking dogs, chainsaws, the neighbor's table saw, utility trucks, the street sweeper, the train south of town, and you have the soundtrack for our very urban owls. They appear to be almost completely unperturbed by all of it.
When Boyle was living in the nest box alone, before DerOwl Hannah showed up, we'd watch him at dusk as he hopped up into the hole and sat for half an hour having coffee, which is to say slowly waking up, eyes half mast, sort of paying attention to the world outside, sort of dozing, until true dark when he would finally awake fully and leave for a night of hunting. Big, loud, jacked-up, coal-rolling trucks would blare past the nest box and he'd just watch with barely a hint of interest, and definitely a hint of disdain.
Countless people walk by on the sidewalk with no awareness of the life-and-death going on in the nest box and trees just above their heads. Last year, once the babies had hatched, DH took to attacking folks who walked too close to the nest. I can tell you from experience that you hear nothing, and you have no idea what hit you, and you think you just walked into a branch or some other overhead thing, except that when you look up after impact, there is no overhead thing there. It was DH nailing you in the head with her outstretched claws, and in my case, pulling my hair out of my ponytail. If you don't know there are resident owls in the area, you have no idea what just happened. (Let the record show, I was NOT getting too close to her nest; I was leaving my house to go get something out of my truck and she must've been hunting in my garden at that moment. I entered the scene, unaware of her presence, and BAM! No more ponytail for me!) At no point during the attack did I hear a thing. There was only silence.
Here's an audio tour of the urban soundtrack that our owls live with, starting with something that probably matches your idea of an appropriate environment for an idyllic, peaceful owl nest: the lovely sound of evening robin song. After that, you might be surprised.