A parabolic microphone works much like a satellite dish does, in that it uses a wide collector area that gathers the signal and focuses it on a smaller area, amplifying the signal as it does so. In this case the signal is not radio frequency, but rather sound.
The collector portion of the microphone can be made from a variety of materials – In this case an inexpensive umbrella hat is used. A microphone is hooked up to a mp3 player with audio input, and the player also serves as a handy audio recorder. This makes the entire setup very portable to carry.
The video shows the before and after effects of using the collector, and the benefits are very apparent. One thing to note, and is note readily apparent in the video, is that the microphone is placed to point towards the umbrella, not the direction of the target. This is because you want to pick up the collected sounds that are focused by the parabolic shape, not the straight sounds waves. All said, a quick and fun project to let you explore your audio surroundings.