I've noticed that I can hear my neighbors when they're talking loudly into the doorbell box in my apartment.
There's a box at the entrance in the hallway that emits the doorbell, and behind it, the wall is hollow. Maybe sound resonates better in a hollow wall?
I managed to hear my neighbor moaning while she was having sex with her boyfriend by putting my ear right up to the intercom.
Do you think that if I put a microphone "in the wall" (behind a wall outlet, for example, in the same spot), I could pick up sound properly?
For that, I would need a small, good-quality recording device (5cm maximum).
1) Do you think such a device exists?
2) Do you think it would work?
3) I would need something with a long battery life, or that I could even activate remotely so I don't have to open the box every time.
Any advice ?
