Lavalier microphone

A lavalier microphone or lavalier (also known as a lav, lapel mic, clip mic, body mic, collar mic, neck mic or personal mic) is a small microphone used for television, theatre, and public speaking applications in order to allow for 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 kept in a pocket or clipped to a belt, or routed directly to the mixer or a recording device.

These miniature microphones are often supplied with a choice of push-on grilles of differing lengths that provide gentle high-frequency boost by forming a resonant cavity. A peak of approximately 6 dB at 6–8 kHz is considered beneficial for compensating loss of clarity when chest-mounted, as is 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.

Lapel microphones date from 1932. Various models were made, including ones with condenser diaphragms, ribbons, moving coils, and carbon buttons. The term referred to any small microphone that could be hooked into the buttonhole of the lapel of a coat. The lapel microphone offered freedom of movement.

The term lavalier originally referred to jewelry in the form of a pendant worn around the neck. Its use as the name of a type of microphone originates from the 1930s, when various practical solutions to microphone use involved hanging the microphone from the neck. For instance, a Dictaphone microphone could be suspended on a belt around the neck in order to retain some degree of freedom of movement while recording one's voice onto a wax cylinder in 1941. Telephone operators and air traffic controllers used microphones that rested on the chest and were secured by a strap around the neck. In the 1950s, some microphone models were designed to be hung on a string around the neck. In 1953, Electro-Voice introduced the Model 647A, a small omnidirectional dynamic microphone fitted with a cord to go around the neck. The body of the 647A was lightweight at 2 ounces (57 g) and relatively small at 0.75 inches (19 mm) in diameter and 3.63 inches (92 mm) in length. In 1954, Shure Brothers offered the larger 530 Slendyne, which could be handheld, mounted on a microphone stand, or worn around the neck on a "lavalier cord."

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