Common Wall Blues
I have a townhouse and when I play my reference system at a moderate volume, my neighbors tell me they hear the bass through the wall. My system is placed on the common wall and the speakers are right at three feet from the back wall and at least four feet from each side wall. Moving the system is not really an option. To try and eliminate the problem I removed all the sheetrock on the common wall, mounted five rows of sound isolation clips to the studs, steel hat channel mounted to the clips, and two layers of sheet rock, with green glue between the layers, mounted to the hat channel. Around the entire perimeter an acoustical sealant was applied. Sound isolation putty was applied to each electrical box. So now the common wall behind my system wall is physically detached from the studs and has greater mass. I did not address the ceiling or the adjacent room also along the common wall. As per the building code, the buildings are constructed with a 2 x 4 insulated stud wall on my side, a narrow air gap, and a 2 x 4 insulated stud wall on my neighbors side. There are no shared features like HVAC ducts, plumbing or electrical. This was a rather costly project and one that has only moderately worked. As such, I turn the volume way down when my neighbors are home so as not to bother anyone. I would like to play my system at a nominal audiophile volume level at any time I like and was wondering if there might be any other options available to me. I do not really want to do any further construction or move. If there are any suggestions I would very much appreciate hearing them. Thank You.
The common cement floor makes for excellent sound transmission, unfortunately. The studio pro way would be to build a floating sub-floor that is sonically isolated. It is an expensive solution. You could try building "mini floor isolation units" under your speakers - my closed cell foam trick that I use under my desktop subwoofer is a "red-neck engineering" approach that will give you some isolation, tube traps will possibly lower the overall amount of sound, but won't help isolate. — StevenStone January 04, 2013 10:11 a.m.