I was just talking to my next-door neighbors who mentioned that they (couple with a new baby) can hear some of my late-night gaming sessions through the wall. I’ve been playing Half-Life 2 Episode One (awesome, btw) with a pretty meaty 5.1 sound system (Logitech z-5300e - 560w peak) but I was surprised to hear that the sound is bleeding given that there’s an entire buffering room between where I’m playing and the adjoining wall. But I guess it is.
My theory is that the sound from the subwoofer is resonating through the house structure. Is there any way to dampen this effect? Right now my sub is sitting directly on the carpeted floor under my desk - would placing it off the floor on some kind of stand like a small table have any effect in dissipating the sound so I can game without annoying my neighbors? It’s either that or turn down the volume which is clearly absurd.
Resonant effects of this type are very common, and it may not just be the sub, depending on how your satellites are set up.
I’d first experiment with placing the sub somewhere else. The current location may be the culprit. The problem with low frequencies is that problems are often not just the subwoofer, but the room itself. Sometimes just moving the subwoofer helps.
If you want to insulate the sub from the floor, you’ll need at least four inches of material, if not more.
It would make more sense to just turn down the subwoofer volume than it would to wear headphones, if the subwoofer is really all they are hearing. When I game on my 360 late at night I usually turn the subwoofer volume on my Logitech z-5450s down to about 2 bars instead of the usual 5 or 6.
Check out the various soundproofing materials that are available, normally used in studios and the like (materials like Sonex). They’re very good for low frequency damping as well, but it won’t be a cheap solution. I spent quite a few days at a home-based recording studio many years ago, and despite ear-bleeding sound in the room itself, you could hear virtually nothing in the room below. I think the guy’s soundproofing bill resembled my phone number though.
As was suggested above, just getting it off the floor and turning it down a bit will go a decent way towards cutting down on the sound transmission. Putting it on a reasonably isolated stand is a start.