Hey D-Man
The old fashion, cheap way is to glue egg boxes onto the walls. It has the added benefit of a cheap high for a couple of weeks when you're in the room, ha ha.
If you wanna go a step further, then also get some lengths of cheap wood and frame the room with them - like a picture frame - at the ceiling and the corners of each wall. You want the wood to be about 3 inches thick. Then get hold of some old carpeting and nail it onto the frame, so that there is a 3 inch gap between the carpet and the walls. The sound gets deadened by the carpet and trapped in the space between the carpet and the wall.
Used that combination with an old band of mine that rehearsed in the guitarist's garage opposite a school and you couldn't hear anything unless you got to within a few metres of the garage.
The old fashion, cheap way is to glue egg boxes onto the walls. It has the added benefit of a cheap high for a couple of weeks when you're in the room, ha ha.
If you wanna go a step further, then also get some lengths of cheap wood and frame the room with them - like a picture frame - at the ceiling and the corners of each wall. You want the wood to be about 3 inches thick. Then get hold of some old carpeting and nail it onto the frame, so that there is a 3 inch gap between the carpet and the walls. The sound gets deadened by the carpet and trapped in the space between the carpet and the wall.
Used that combination with an old band of mine that rehearsed in the guitarist's garage opposite a school and you couldn't hear anything unless you got to within a few metres of the garage.