I've called the cops on my neighbors before. I tried to go over there and tell him to please turn it down. The music was so loud, he didn't hear me knock on the door...two different times! I understand it was New Year Eve, but that loud, that late was too much for me. I called the cops. The loud music came down, but then I heard him banging on the wall randomly. Mind you, I've been having problems with him for a while.
My current neighbor, same thing. I kept going over there constantly to ask him to turn the music down. I told him I work from home and I lose productivity when it's that loud. So we made an agreement, which he pretty much stuck to. Over time it hasn't been as bad and it's quieter. I was to the point of calling the cops too, but because he actually did turn it down when I complained, I didn't make the call. Also, our homes are detatched! We have a good amount of space between us, it shouldn't be that loud, and it was mostly the bass I beard.
I also had that issue in college. I'm sorry, I have an 8am class on Friday, so a 3 in the morning partying doesnt work for me.
I'm pretty quick to complain. I DO NOT like to have my sleep interrupted in that manner.
I felt like that was a much needed vent...