Posted by John Swensen on August 17, 2000 at 13:49:07:
In Reply to: Kleenex and Spit posted by Rick Denney on August 17, 2000 at 11:49:25:
Rick,
To put it bluntly, you will only soundproof your basement by blocking every path from your tuba to the outside with mass (preferably limp mass). The concrete walls of your basement are doing a good job, but the sound (mostly low frequencies) is going through the flooring, joists, windows, and any other openings to the outside world. Sound has the irritating property of finding any leaks in the room and escaping there (much like high voltages finding leaks in insulation). If you had a piccolo, the fiberglass would be helping dampen the sound reverberation (as well as some of the transmission), but you don't, and it is providing only a duller sound within your basement.
The cheapest solution would be to find a corner of the basement for your studio and build a room there. Hang sheetrock from the floor joists above, tape and seal all cracks, then build a complete room, not touching the existing walls or ceiling, sheetrocking the studs and taping and sealing all joints. A better solution involves building a double-walled room, either by using a 2x6 plate with offset 2x4 studs, or by having two sets of studs and plates, with one layer of sheetrock on one wall, a double layer on the other wall. Air can be provided via insulated, flexible ducting with one or more 180 degree bends in each (one for air in, another for air out), and with the ducts suspended, not touching either the room walls, the surrounding structure, or each other; you may require a small fan to ensure air circulation.
Tab books has published a few books on studio acoustics (written by Everest, I believe),
that have practical advice on achieving better soundproofing. If you want to get more theoretical, Beranek has written and edited a few books on the subject.