A microphone is a device that converts acoustic power into electric power. Both the acoustic power and the electric power have similar wave characteristics that convert sound waves into electric voltages that eventually convert back into sound waves through speakers. Microphone were used with the first telephones, and then with radio transmitters soon after.
Sir Charles Wheatstone was the first person to come up with the word “microphone” in 1827, but even so, it was Emile Berliner who invented the first microphone in 1876. Emile Berliner was born in Hanover, Germany in 1951. When he was 19, he moved to the United States in Washington. When he got there, he studied physics part time at Cooper Institute (now known as Cooper Union). Berliner helped out in the chemical laboratory and spent most of his time functioning as a seller of consumer dry goods. When Alexander Graham Bell introduced the first telephone at the U.S. Centennial Exposition, many inventors had a mission to improve this new revolutionary invention. Berliner, like everyone else, was fascinated with the telephone but had no means to improve it. Then a telegraph operator told him that more current passed as one pressed harder on the key and Berliner was suddenly inspired. He wanted to discover a way in which sound can be recorded and repeated.
In 1876, the 25 year old invented the gramophone, and then later the microphone as a telephone voice transmitter. The microphone became widely popular as it recorded sounds out of speakers at a volume louder than the ordinary human voice. The Bell Telephone Company was extremely impressed with the invention and later bought Berliner’s microphone for $50,000.
In 1878, David Edward Hughes invented the first carbon microphone, which later was improved during the 1920’s.
In 1964, James West and Gerhard Sessler from Bell Laboratories invented the electret microphone. The electret microphone had greater reliability, higher precision, lower cost, and a smaller size. The invention made an impact in the microphone industry with more than one billion being manufactured each year.