Those trucks' brakes don't quite sound like most other brakes I usually hear. They drift a little closer to beign musical than most brakes. It's two notes, to be exact, at least to my hearing. And it's a usually quiet neighborhood, so it's not competing with much noise. Yes, there's train noise from the Brooklyn Rail Yards several blocks over, but from this distance that's not a constant noise. It adds to the noise flavor. As do the trucks.
This is about as much thought as I'm capable of right now. Slightly wearying day and night, yesterday, plus dreams that unsettled and saddened me a bit. So, now, I do my best to absorb calm. Which partially, somehow, comes from truck brakes.