When my wife was pregant before, we met such case. First we went to talk to them directly (They had party at Friday night), but they didn't change anything with very bad attitude. Then after couple of ten minutes, I called 9-1-1- and police came after 10minutes and knock their door and told them to be quiet. And them polic came to my apartment to say he had talked to them already.
In past several years, I had called 9-1-1 twice with two different places(apartments) for the same reason regarding the neigbourhood noise in late night. And police all came to intervene.