Unfortunately, I think your requirements will preclude being able to attenuate a lot of sound transmission.McEvil wrote:A) Doesn't require a lot of structural/hard-to-remove changes? This is a rented apartment that I do not intend to keep.
B) Can be moved to new locations with relative ease? I'm fresh out of college and will be a bit of a nomad until I settle down years from now.
Generally, heavy, well-damped things absorb sound. That's why a "soundproof" wall uses staggered studs or even two walls, with a damping material between them. Or two sheets of wallboard with a damping material between them.
You don't want to line the room with foam. That changes the sound reflected back to you, not the sound that is transmitted through the walls.
There is one approach that might be enough. Go buy enough cheap bookshelves to completely surround a practice space(preferably they could stand away from the nearest wall a couple of inches), and then go to one of these used-book stores that sells books by the yard to interior designers. Stuff those shelves full to the top. Then, lay a sheet of plastic over the top of them, followed by 2x4's that will span the opening placed across the top of the shelves. Lay a cheapie big thick rug across the top of the 2x4's, and staple the plastic to the underside. Lean a mattress up against your access opening so that it touches on all edges.
I don't know what you'll get in terms of attenuation. But it might be enough to reduce the effect below the annoyance level. It will be very much cheaper than a pre-fab practice cubicle, and it will move just like all your other stuff.
Oh, and be nice to your neighbors. Make deals with them about when it's okay to play, and stick to what you agree to.
Rick "who moved across the county in part to get away from demanding tuba-hating neighbors, and that in a house, not an apartment" Denney