Hah, if half of the suggestions here are serious then half of the people attending these forums are more childish than I thought

don't fight fire with fire by being loud, fire likes to spread and in this case noise is the fire and your neighborhood is the forest, you don't put the forest out by lighting up even more trees. As for asking them to be quiet you seem to be a bit intimidated by them but I would rather go and ask them if they could be quieter in a nice way and if they keep being loud you can come and ask them to be quieter with a warning that if they keep it up you will call the police or whatever other more appropriate authority you can think of to handle the situation. And of course if they then keep it up or even if they just act rude the first time around then the 3rd time (or 2nd if they made it clear they weren't going to be silent the first time around) you call your authority of choice to handle it.
People who act this way only get away with it because the people around them think they will take drastic measures if they do something about it but in most cases those kind of people are all bark and no bite since they know as well as you do that they can get in some big trouble if they actually do anything in retaliation.
I have a neighbor who lives in the apartment beneath mine who was pretty loud when he first moved in but I only needed to give him a single visit and he's been quiet since. Just be prepared to call them out on their crap and have an appropriate response ready if they decide to play that "oh but you were loud once too" card or if they try to act intimidating, a lot of people will try to win an argument just by catching you off guard and the moment you ponder any question for even a second or show that you feel they are intimidating is where they start thinking they can just slam the door on you and not hear from you again.