Far Away Train

It's weird how sound travels in the nighttime. I am not particularly close to a train track, but I heard the sounds of trains for awhile last night as I was trying to fall asleep. I don't understand why. I've heard them before, but this was particularly loud, as if some atmospheric phenomenon was bouncing the soundwaves right into my bedroom.

There are a variety of sounds that I understand all too well, and I'd like some sort of sonic self-defense weapon. I've heard that the proper sound wave sent back to the speaker will cause it to break. That requires analyzing the sound that's hitting my house first, similar to what's done with sound cancelling devices. I'd be happy with a sound cancelling device too, assuming it could cancel sound that makes my house shake. Right now most of these sound cancelling devices are just headphones.

The guy who figures out how to do this with a whole house stands to make a lot of money. Cancel the sound as it passes through the walls. Imagine being able to do that for everything, from the musically challenged driving by your house, to the airplanes overheard, and even the trains that inexplicably sound off in your bedroom.