After the day's chaos settles down, an ambient lullaby lulls the city to sleep. It's a wonderfully ordinary collection of sounds -- a lonely dog whining on a back porch, a loose muffler sputtering up a hill, the nearby thunk of a car door, the distant wail of a siren. And sometimes, you'll hear a song coming from somewhere nearby. Maybe this one. Or this.
Or maybe nothing at all except your own footsteps on the sidewalk.