Neighbor involvement
There is no doubt that whatever is happening to my home is controlled by my neighbor. Not solely her as I've experienced the same in the last few apartments, but she has control of the weapon now. I went on a little staycation in my city and came home around 10pm. Neighbor was asleep, I guess, and my apartment sounded and felt NORMAL. No vibrations, headaches, infrasound, loud thumps, or engines revving that can literally knock me and my dog over the head. Usually the weapon is the strongest at night when I try to sleep. I'm guessing she went to bed and thought I'd be gone another night. As soon as she woke up at 7:30am somehow she knew I was home and turned on the weapon. It was like clockwork. It is something that magnifies the acoustics of the building, or mimics that effect so anyone complaining about it seems like it's just in their head. I've previously told her the noise seems to only happen and get worse when she's there, not when she has someone there for airbnb or whatever. She told me she "can't help the acoustics of the building"... I hadn't phrased it like that before, but now I have a clue to find an acoustics engineer to investigate this!