Need a good audio set for an apartment

[Clippins]

Ok so I'm going to be moving into my first ever apartment on Saturday. 30 and recently divorced...no need to go into the story but that's why going from house to apartment. I would like to piece together a nice audio setup, including receiver and speakers, but I don't want to get the neighbors all angry. I've currently got a Bose 3-2-1 system which is probably perfect for an apartment but honestly I think the Bose 3-2-1 is completely bushleague. So I would like some advice what would be a good receiver and speaker combo to get on a mid to low level budget for an apartment? I'd imagine a sub would be out of the question, or would it be? I've got to imagine there's some other apartment dwellers here on these forums. Any issues with making your neighbors upset with what audio equipment you run?