Invention of the telephone
The carbon microphone was independently developed around 1878 by David Edward Hughes in England and Emile Berliner and Thomas Edison in the US. Although Edison was awarded the first patent 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.
Georg Neumann
In 1965 Neumann began to introduce solid-state microphones. The first model was the KTM small cardioid, later followed by the "fet 70" series—transistorized versions of small omnidirectional, cardioid and speech cardioid microphones as well as a "U 77" transistorized version of the U 67. This series used the 12-volt A-B powering system (parallel powering, T-power or "Tonaderspeisung") as found in Nagra tape recorders, and was therefore incompatible with existing studio power supplies. However, standard two-conductor shielded cables (as were commonly used for dynamic microphones) could now be used for connecting condenser microphones as well, obviating the need for special multi-conductor cables.