Using a speaker as a microphone is a trick old enough to have become common knowledge, but how often do you see the hack ...

James West is the co-inventor of the electret microphone used in telephones, sound recording devices, hearing aids, and other products. A research professor of electrical and computer engineering and ...

Microphones can be found just about everywhere nowadays. Most people reading this article will have a cell phone in their pocket which uses a microphone to transmit an audio signal to other phones all ...