|
RCA Type 44
The RCA Type 44 microphone is a bi-directional ribbon microphone, or pressure-gradient microphone, first introduced by the RCA Corporation in 1931. History Dr. Harry F. Olson began working for RCA Laboratories, where he developed ribbon microphones, first with field coils and then with permanent magnets, resulting in the first ribbon microphones with bi-directional pickup pattern, the RCA Photophone PB-17 and PB-31, introduced in 1931. The PB-31 was employed by Radio City Music Hall in 1932. Also in 1931, RCA introduced the Type 44-A Velocity Microphone. A smaller and lower-priced version of the uni-directional Type 77-A, the 44-A's smooth sound and defined pattern control reduced the effect of reverberation on soundstages and offered higher gain-before-feedback in live sound applications, making it a staple of the audio recording and broadcasting industries. In 1940, RCA updated the Type 44 with improved magnet material to introduce the Type 44-B and Type 44-BX. The 44-B and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribbon Microphone
A ribbon microphone, also known as a ribbon velocity microphone, is a type of microphone that uses a thin aluminum, duraluminum or nanofilm of electrically conductive ribbon placed between the poles of a magnet to produce a voltage by electromagnetic induction. Ribbon microphones are typically bidirectional, meaning that they pick up sounds equally well from either side of the microphone. Principle of operation In a moving-coil microphone, the diaphragm is attached to a light movable coil that generates a voltage as it moves back and forth between the poles of a permanent magnet. In ribbon microphones, a very thin light metal ribbon (usually corrugated) is suspended between the poles of a magnet. As the ribbon vibrates, a voltage is induced at right angles to both the ribbon velocity and magnetic field direction and is picked off by contacts at the ends of the ribbon. Ribbon microphones are also called "velocity microphones" because the induced voltage is proportional to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RCA 44 Of CBS 20071104
RCA Corporation was a major American electronics company, which was founded in 1919 as the Radio Corporation of America. It was initially a patent trust owned by General Electric (GE), Westinghouse, AT&T Corporation and United Fruit Company. In 1932, RCA became an independent company after the partners were required to divest their ownership as part of the settlement of a government antitrust suit. An innovative and progressive company, RCA was the dominant electronics and communications firm in the United States for over five decades. In the early 1920s, RCA was at the forefront of the mushrooming radio industry as a major manufacturer of radio receivers, and the exclusive manufacturer of the first superheterodyne sets. The company also created the first nationwide American radio network, the National Broadcasting Company (NBC). RCA was also a pioneer in the introduction and development of television, both black and white and especially color television. Throughout most of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
