RCA BK-6B Moving Coil Miniature Dynamic microphone, 1957.

RCA BK-6B is a moving coil miniature dynamic microphone, designed for speech.

This BK-6B example was used by the BBC and has been set up for use as a lavalier microphone, with an original RCA neck cord and cylindrical metal bracket, this allowed it to be hung round the neck. It is engraved BBC No. 236.

The BK-6B was designed for the correct speech balance when used in television broadcasting and public address applications. The frequency response and directional characteristics mimicked human voice: high-pitched nasal sounds emitted in a narrow angle from the front of the face and less directional low-pitched sounds from the throat and chest. The small size allowed it to be easily concealed in a hand or in clothing, for example during an interview.

The design was conceived to be appealing, whilst blending with surroundings. It was promoted with the nickname “PEEWEE” microphone.