How a Parabolic Microphone Works
Parabolic Microphone
A parabolic microphone is a special kind of microphone that can focus on a sound source, even one that is far away, and enhances it so all the other sounds and noises from other sound sources are minimized or totally blocked out. This capability of this kind of microphone makes it ideal for recording voices for music purposes or even for spying purposes.
How Parabolic Microphones Work
The physics behind parabolic microphones revolves around parallel waves of sound being collected and directed to a single specific point. This kind of microphone features a design where a parabolic reflector captures parallel waves of sound from a specific source and focuses it into a single and stronger point, making the sound clearer and easier to hear. Weak sounds are made stronger by this kind of reflector by how it collects sound waves and how it can focus on a single specific location.
It is actually just a regular microphone that is enhanced by a parabolic cross section device. The design and geometrical properties of the parabolic device make it a powerful amplifying device. The sound waves that pass straight into the microphone is just a normal piece of the overall sound being captured, but the other sound waves that run parallel to it will hit the parabolic dish and will reflect right into the microphone, effectively focusing different elements of a sound source into a single point, hence the amplified quality of the sound.
The Different Uses of Parabolic Microphones
With its unique ability to capture directional sound, which means it can focus on a specific sound source from the direction it is being pointed at, this kind of microphone has several specialized uses. One of the most popular uses for it is in nature observation. Whether it is birds, lions, chimpanzees or other animals, they can be observed from a distance using this kind of microphone. Their mating calls and other ways of communicating can be recorded without invading their territory. The sound that birds make can be recorded for scientific study even if they are high up in a forest canopy. The sounds of dangerous animals can be observed and recorded from a safe distance. This is why scientists and nature observers find this kind of microphone extremely useful.
In surveillance, this kind of microphone also offers a safe and effective way of eavesdropping and recording conversations from a safe distance and secret location. It is often used by law enforcement agents and spies to do their surveillance work without giving away their position and presence. It can also be used in filmmaking whether it involves feature films or documentaries.
Conclusion
A parabolic microphone is indeed a very useful device for capturing sounds in a directional manner. If you want to get a good idea of how it works before buying one, you can place your open hand behind your ear with the palm facing forward. You will notice sounds are louder, and that is basically how this kind of microphone works.
References
Britannica, https://www.britannica.com/facts/5/527219/parabolic-microphone-as-discussed-in-sound-physics
Defense Devices, https://www.defensedevices.com/parabolic-microphone.html
Photo Courtesy of <em>Wikimedia Commons; Creative Commons Attribution / Supplied by JGlover</em>