Hi Todd,
The responses here are all accurate and I'd agree that Jason's suggestion is the best recourse.
However, I think it would be prudent to go with the 500 rather than the 600. The 500 doesn't go quite as low in frequency as the 600 and has a bit less total output, so it's more manageable. You'll still be thrilled with the low frequencies and overall performance of the 500.
Short of building a room within a room, which is impractical in your situation, Jason's suggestion is best. Find out when they tend to be away or out, so you can crank it up!
Regards,
