Useful Tips

How to eavesdrop and record other people's conversations behind the wall


Are you curious about what is happening on the other side of the wall? Are you interested in listening to this? Whether it is a stranger or a close person, this happens in your house or in some other place, but in any case, spying on another person is not very noble. If you still decide to eavesdrop, then there are several ways to hear everything that is happening clearly and clearly. Be aware of all the risks and criminal liability before committing such an act.

Method 1 Using a Glass

  1. 1 Take a glass. So, you still decided to go for it. How to start spying? The easiest way is to attach the glass to the wall. An “acoustic connection” is created between the wall and the glass, which allows sound waves to pass from one side of the glass to the other. A glass for soda or beer is best. Some spies swear that cardboard glasses are great for these purposes, but glass conducts vibration of sound waves much better than other materials.
    • Experiment with different types and shapes of glasses to determine the most suitable for your goals.
    • If you're a lucky iPhone owner, you can download the Amplitude Pro app and keep it near a glass against the wall. This application not only allows you to hear distant sounds much more clearly, but also can record and save them.
  2. 2 Explore different parts of the wall to find the best point. In some places on the wall, sound will be transmitted better. This is due to the uneven structure of the wall or due to different distances from the sound source. Check the sound quality at different points until you find the best place. This can sometimes be difficult, especially if you need to eavesdrop on the ceiling. If you are too far from the wall, the sound will not be heard clearly enough.
  3. 3 Lean the edge of the glass against the wall. Remember that in order to achieve an acoustic effect you need to place the glass against the wall. Do this by placing the glass flat rim against the wall. Now the acoustic waves go from the wall to the glass, during which the sound is amplified.
    • Immediately after applying the glass to the wall, you should lean your ear to its bottom. Move the glass along the wall if the conversation is not well heard.

Method 2 Using a Hole

  1. 1 Make a small hole in the wall with a drill. Scientists from South Korea and Japan discovered this option of eavesdropping through walls using a hole and a plastic membrane. To begin, drill a small through hole in the wall. A long and thin drill is best suited.
    • Do not expect to hear too much through just one small hole. In fact, a single hole seriously interferes with the transmission of sound.
    • Try to drill a hole at a time when your neighbor is also working with a drill. Otherwise, he may notice drilling debris and hear a noise.
  2. 2 Cover the hole with a thin membrane. So you dramatically improve audibility. Studies show that when you cover a hole with a thin membrane, you improve the sound transmission so well that you get the impression that there is no wall at all, because the membrane equalizes the pressure on both sides of the hole through which the sound passes.
    • Try to use for this purpose the plastic film available in each house. Scientists at the initial stage of the study used just such a film.
  3. 3 eavesdrop. As soon as you get a hole covered with plastic wrap, start listening! With the correct implementation of our instructions, you will clearly hear everything that happens behind the wall.
    • To achieve the best effect, you can combine this method with the first. Place the glass over the hole with the membrane.
    • Remember that the method of drilling holes has its drawbacks. Your neighbor can hear a sound, notice a hole in the wall or debris that will remain after drilling and suspect something is wrong. Do everything very carefully!

Method 3 Using a Spy Stethoscope

  1. 1 Assemble the necessary components. Now we will use more specific spy equipment. You can make a stethoscope at home or buy it. The finished product will save you time, but you will have to spend several hundred dollars. A homemade stethoscope will cost you less than $ 25, but this is subject to the availability of a good MP3 player.
    • You can buy a regular stethoscope at a local pharmacy for about $ 10. The quality of a stethoscope is unlikely to play an important role.
    • You will also need microphones. It is best to buy stereo multimedia microphones, as they are very cheap (around $ 15), but have good sound settings. With them you get a sound of good enough quality.
    • And finally, you need an MP3 player to record sound, as well as a cable with a 3.5 mm plug. The cable will cost you about 3-4 dollars. If you do not have a suitable MP3 player, then in this list it will be the most expensive purchase. Keep in mind that the player must be able to record sound, which means that you will need a more modern model (most older models only play music without recording sound).
  2. 2 Disassemble the microphone. You will need to open the microphone housing to get to the wire, then remove the cover and get the microphones themselves. Then insert the extracted microphones into the headphones of the stethoscope.
    • The most suitable tool for this is the X-Acto knife. He will make a straight cut that will allow you to get to the contents. You should get 2 microphones and a 3.5 mm plug (cable) each.
  3. 3 Disassemble and reassemble the stethoscope headphones. Remove the headphones from the stethoscope. It is easy enough. They should be removed with a little effort. Do not discard the headphones, as you will need to install microphones in them.
    • Then you need to drill a small hole in the plastic earphone, which will correspond to the diameter of the microphone body. The diameter of the holes should be done accurately, since the microphones must be held tightly inside. A drill or engraving machine will help you cope with this task.
    • Glue the microphones inside the headphones. Apply a little glue to the edges of the microphone housing, and then insert them into the holes made. Put the headphones back on the stethoscope and let the glue dry.
  4. 4 Attach a stethoscope to your MP3 player. Finally, attach a stethoscope and microphones to your MP3 player. Sound coming from behind the wall will be amplified by microphones, transmitted to an MP3 player and recorded.
    • Connect the resulting stereo cable to an MP3 player. Your spy stethoscope is ready.
  5. 5 Start eavesdropping. To get started, test your stethoscope. As with an ordinary glass, first you have to experiment, find the best place on the wall and check the quality of the recording. If the experimental wall does not have double glazing or thick insulation, then you should hear everything that happens behind it.

Method 4 Find Out Possible Implications of Spying

  1. 1 Ask yourself, do you really want to spy? Listening to conversations behind the wall, you violate the personal space of people. This leads to legal and ethical issues. Before starting espionage, think seriously about whether it is worth the risk?
    • The situation can be very unpleasant. In England, for example, a man saved his neighbor from robbery when he was drying through a wall with a glass. In his case, espionage was acquitted.
    • However, the situation is controversial. Do not do this if you have no good reason. But if you still decide, then you should be aware of the possible consequences.
  2. 2 Study the laws regarding eavesdropping. Espionage is considered to be eavesdropping, recording, as well as the transfer of any part of a personal conversation without the consent of the people involved. Be aware that the state has created eavesdropping laws. Spying on others, you can become a violator of the law, you also break the law, if you simply own a listening device.
    • Your state may have a law "by agreement of one of the parties" or "by agreement of both parties." By agreement of one of the parties, it is illegal to eavesdrop on someone else’s conversation only if you do not have permission from one of the participants in the conversation. By agreement of both parties, it means that you need to get permission from both parties to listen and record the conversation.
    • Take for example the state of Michigan, USA. Michigan has a “consent of both parties” law, so even if the conversation is in your own home, you must have permission to “listen to a private conversation, record it and transfer any information to third parties.” Eavesdropping is considered a crime.
  3. 3 Consider the negative effects. What happens if someone finds out that you are eavesdropping? What could happen to you? This is a good question and you should consider all the possible consequences, which in many cases are serious.
    • In Michigan, the punishment will be 2 years in prison or a fine of $ 2,000, or both. In California, eavesdropping can be considered misconduct or crime. You can be imprisoned for 364 days for a misdemeanor, as well as fined $ 2,500, and as a criminal offense, you can be imprisoned for 3 years and fined $ 2,500.
    • However, criminal punishment is not the only bad outcome. They may also file a lawsuit against you for violating your privacy and demand compensation in the amount of several thousand dollars. Even if you manage to avoid legal consequences, next to yourself you can end up with a very embittered person.

What do you need

For the method with a glass:

  • Glass
  • Wall
  • iPhone with Amplitude Pro app (optional)

For a spy stethoscope:

  • Stethoscope
  • Stereo multimedia microphones
  • Cable with 3.5 mm plug
  • X-Acto Knife (or similar)
  • Small drill
  • Glue