Lavalier microphone



A lavalier microphone or lavalier (or lav or lapel mic) is a small electret or dynamic microphone used for television, theatre, and public speaking applications, in order to allow hands-free operation. They are most commonly provided with small clips for attaching to collars, ties, or other clothing. The cord may be hidden by clothes and either run to a radio frequency transmitter in a pocket or clipped to a belt (for mobile work), or directly to the mixer (for stationary applications).

These miniature mics are often supplied with a choice of push-on grilles of differing lengths which provide gentle high-frequency boost by forming a resonant cavity. A peak of around 6 dB at 6-8 kHz is considered beneficial for compensating loss of clarity when chest mount  ed, and a peak of a few decibels at 10-15 kHz when mounted in the hair above the forehead. This method of boosting high frequencies does not worsen noise performance, as electronic equalization would do.

History
The term lavalier originally referred to a pendant worn around the neck. Its use as the name of a type of microphone dates from the early 1960s.

An American electrical engineer with Educational Media Resources and San Jose State College, Raymond A. Litke invented the wireless microphone in 1957 to meet the multimedia needs for classroom delivery. His U.S. Patent No. 3, 134, 074 filed May 6, 1961, (originally filed Jan. 8, 1960) is the first portable, workable, practical and dependable wireless microphone. The diagram illustrates the cigar-sized device which was six inches long and weighed seven ounces including a power supply and transmitter. Impressed by the more than one-half-mile distance of transmission, the FCC granted Litke 12 frequencies at his approval hearing. Litke coined the term “lavalier microphone” a word which appears in his patent.

Also called the Vega-Mike after Vega Electronics Corporation which first manufactured it in 1960, the midget device was used by the broadcast media at the 1960 Democratic and Republican conventions. It allowed reporters to roam the floor of the convention to interview participants where Presidential candidates Kennedy and Nixon were the first celebrities to use the wireless microphone. The American Broadcasting Corporation (ABC) completed testing in 1959 and 1960, prior to the convention. Television anchor John Daly was exuberant with his praises for Litke's invention. The wireless microphone was also tested at the Olympic trials held at Stanford University in 1959.

In newspaper articles from both the San Jose News of Sept. 10, 1960, and The Alma Signal-Enterprise (KS) dated Nov. 10, 1969 and Feb. 26, 1981, Litke attributes the inspiration of his invention to the winged communication of the bee. Although electronics experts and scientists told him the wireless microphone was an impossibility, despite that discouragement, Litke managed to invent the microphone in 1957. This wireless microphone was only one of Litke’s inventions. In the 1960’s Litke was employed at University of California Medical Center in San Francisco where he invented some medical instruments including the fiber-optic colonscope.