I completely forgot about how I handled a noisy downstairs neighbor in N. Cape May, NJ back in 1976. My wife and I, with our 1 year old daughter lived upstairs in an apartment building (at least we had the end unit; our next door neighbors upstairs were always very quiet.
I was in the Coast Guard as was our downstair's idiot, oops I mean neighbor. We shared a common entrance door into a small vestibule; then we each had our own locking apartment door, ours leading to the flight of stairs up to the apartment.Think of this stairwell as a noise amplifier.
They always left their front door partially open possibly a bad latch but every time my wife or I would enter the vestibule he'd make a point of slamming the door, so hard, that we almost had a framed picture or two fall off the wall. My father-in-law had worked for AMPEX and had a reel to reel and cassette tape library that would make a record store jealous. In particular interest to me were the sound effects tapes he had! He had also given me a pair of speakers, about 4" cubed with a magnet 2-3 times stronger then one would expect. They also had long cables...long enough to dangle outside a bedroom window on the first floor.
I don't know how the sound of a steam locomotive, pulling a freight train past a fixed point affected him, but the door slamming stopped for a few months.
Not that this chap was an idiot but the last straw was one evening when my wife asked me if I smelled smoke...looking at the stairwell I saw a cloud of smoke rolling up the stairs. I told my wife to take our daughter and immediately get out of the apartment. Following them down the stairs - well the idiot's apartment door was open a hair or two and the apartment was full of smoke. As I was yelling for anyone in the house - from a bedroom comes idiot, tying a robe around his waist, and saying, "my dinner!" Dumbass put food in the oven and went to bed...to sleep. I tried to stop him from opening the oven door, trying to make sure his family got out of the apartment...but he opened the door...singing his eye lashes completely!
The local volunteer fire department couldn't believe just how stupid he was. A week later the Coast Guard moved us to a safer location, a brand new house!