BillFitzmaurice.info

Reading a Quora post about sound isolation

https://www.quora.com/Why-is-it-so-easy ... wn-bedroom

gave me a "brilliant" idea: Install a mic between the first floor ceiling and second level floor, run the signal through a signal inverter (whatever sound cancelling tech uses), then run that to a small amp and subwoofer, separate from your regular HT / stereo system. When the painfully noisy upstairs neighbors start stomping around, flick on the unit.

I know, I know: a whole lot of work. But, WOULD it work, and if so, how effective could it be?

I've read and participated in the threads here about decoupling, second sheets of drywall, adding mass (Dynamat etc), the rubber foot mounted on rails technique, separate but nestled studs, etc. This is for a problem I had at an ex gf's condo that she couldn't afford to move from at the time.

Regarding the link, "Sound gets through material by having one molecule push on another", that's not quite right. Sound doesn't get through solid material. Sound waves cause solid material to vibrate. If there's sufficient energy it will vibrate enough to create sound waves on the other side. The easiest way to stop sound transmission is to make a wall, ceiling or floor stiff and/or heavy enough so that it won't vibrate. That's where double layers of drywall etc. come into play. As for noise cancelling, that only works within a short distance from the microphone and the speaker playing the polarity inverted signal. With headphones it's easy, with a house or even just a room not so much.

A few other possible solutions...