"The Marconi Skykes" or "magnetophon", developed by Captain H.
Wente of Western Electric developed the next breakthrough with the first condenser microphone. In 1923, the first practical moving coil microphone was built. Although Edison was awarded the first patent (after a long legal dispute) in mid-1877, Hughes had demonstrated his working device in front of many witnesses some years earlier, and most historians credit him with its invention. The carbon microphone is the direct prototype of today's microphones and was critical in the development of telephony, broadcasting and the recording industries. Thomas Edison refined the carbon microphone into his carbon-button transmitter of 1886. This microphone was employed at the first ever radio broadcast, a performance at the New York Metropolitan Opera House in 1910. This was independently developed by David Edward Hughes in England and Emile Berliner and Thomas Edison in the US. The first microphone that enabled proper voice telephony was the (loose-contact) carbon microphone. Better results were achieved with the "liquid transmitter" design in Scottish-American Alexander Graham Bell's telephone of 1876 – the diaphragm was attached to a conductive rod in an acid solution. These systems, however, gave a very poor sound quality. German inventor Johann Philipp Reis designed an early sound transmitter that used a metallic strip attached to a vibrating membrane that would produce intermittent current. Some of the first examples, from fifth century BC Greece, were theater masks with horn-shaped mouth openings that acoustically amplified the voice of actors in amphitheatres. In 1665, the English physicist Robert Hooke was the first to experiment with a medium other than air with the invention of the "lovers' telephone" made of stretched wire with a cup attached at each end. The earliest devices used to achieve this were acoustic megaphones. In order to speak to larger groups of people, a need arose to increase the volume of the human voice. Microphones typically need to be connected to a preamplifier before the signal can be recorded or reproduced. The most common are the dynamic microphone, which uses a coil of wire suspended in a magnetic field the condenser microphone, which uses the vibrating diaphragm as a capacitor plate, and the piezoelectric microphone, which uses a crystal of piezoelectric material. Several different types of microphone are in use, which employ different methods to convert the air pressure variations of a sound wave to an electrical signal.
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