to make them stop you have a few options ; you could go the angry neighbor and bang on the wall during them getting freaky, and tell them to shut the hell up - very upfront
you could also play the creepy guy ; right after they finish, bang on the wall and yell " KEEP GOING IM NOT FINISHED " .. this will cause them to get confused and slightly freaked out ; avoiding the entire situation to happen again due to eavesdropping neighbors .
Although option B tends to get a very good laugh for a week, in the long run neighbors talk to each other and makes it weird for a while .
But i tend not to care what people think of me ; so i would be "that" guy .