Really this is a big problem. Where i rent now I can hear pretty much everything that goes on on the floor above me, so I'm sure the people below me can hear me too. That has a big impact on me, I can't just let go and sing, experiment etc, so I just hold back when singing. I'm a terrible singer but I feel the need to experiment a bit anyways. What do I do. Any ideas? Where do you guys buy all that foam stuff you put on you walls? Would that help?