How much noise are neighbors allowed to make?

[Adam Bolander]

I've got two questions.  Here's my situation: I used to enjoy renting where I do, but a few months ago my landlords rented the apartment across from me to a family who loves to throw outdoor parties.  They will have these parties almost every night, and a lot of them will go on until after 2 in the morning. They drink, and the more they drink the louder they get. And I never realized how un-soundproof my apartment was until I started having to listen to these guys laugh and yell at each other when I was trying to sleep.  And it's only been getting worse the longer they're allowed to do it.  Last night one of them set up a circular saw and was cutting wood for their bonfire at 9:00 at night.  Thing is, they never yell TOO LOUD, just loudly enough to be a pain to the people in their immediate vicinity, and they don't play music or anything.  I've tried filing complaints about them to the landlords, but they always remind me that I'm not the only one living here so I can't expect complete silence all the time.  But I don't, I just don't want to be kept up at night by my inconsiderate neighbors.  I've even found my landlords out there drinking with them on more than one occaision, so I know they don't a give a crap.

So, here are my questions: how much noise do I have to allow my neighbors to make before it's reasonable to take some sort of action against them?  And two, what sort of action can I take that will either go around my landlords or force them to actually do their jobs?  Would it be easier to somehow soundproof my own apartment?  Thanks!