Hey guys i have a little question here.. Right now we (my band) are rehearsing on our drummers house, but we are having some small problems with neighbors when we are trying to rehearse late at night.. so we want to isolate our rehearsing room.. we know we have to buy some gypsum, but there are a lot of types of gypsum, like depth (in inches we have found 4" and 6") and colors (Grey being the tougher, blue medium one and white really soft), so my question is what type of gypsum should we buy ?? And any other tips on isolating the room will be highly appreciated.. thanks in advance !