Actually a parabolic mic could work, just not as well as in open air. Since it is very directional, it will tend to exclude the noises in his room while picking up sounds coming thru the wall it’s pointed at. Add some amplification and he may be able to hear thru your wall just fine.
In this way, are parabolic microphones illegal?
Most will not consider the use audio filters, like electronic processing to remove extra sounds, amplification of the sounds, boom microphones, parabolic microphones or receivers, etc. to be legal. They claim they run afoul of wiretap laws.
Also Know, how do you listen to neighbors through walls? To hear through walls, start by finding a drinking glass with a wide rim. Then, hold the rim of the glass against the wall you want to listen through and rest your ear on the bottom of it. Sound waves will travel through the wall and into the glass, making it easier for you to hear through it!
Furthermore, does putting a cup against a wall work?
The old classic glass to the wall trick It’s a cliche, but it works. Take a stemless glass and place the open end against the wall. Any sound waves that permeate the wall will resonate inside the glass and your ear will better be able to capture and process them.
Can listening devices hear through walls?
A professional listening through wall device capable of penetrating walls up to 12 inches thick. The highly sensitive microphone and fine tuning noise buffer filter allows you to hear words on the other side of the wall, and you can even record from this clever audio listening bug thanks to a handy output socket.