This is a sound observation of my bedroom

It is always quiet in my room until I focus really hard on the atmosphere around me. The two most obvious sounds that fill the room are the shrilly hum of the bugs outside and the dull, muted humming of the air conditioning. The AC cuts off with a click and a fading hum, and I am able to hear almost the whole building. I can hear the whirring of my roommate's sheets in the dryer, with the occasional clang of the loose screw we have yet to fix. My downstairs neighbor must like rap music, for I can hear the loud bass of the speakers from beneath my feet. The ringing of the bugs song fades in and out, and I hear a dog's sharp bark from outside my window. Later that night, the roar of the insects is slowly overtaken by the rhythmic clanging of the train making its nightly trip by my bedroom window. The grinding and slicing metal is a steady reminder of its presence, even as the sharp roar of the horn fades into the distance and the night. The train fades into a dull hum and the insects overtake the night once again as with their rhythmic, shrill song.