BBC R&D

Abstract

A new electrostatic microphone, type C 12, has been produced by the firm of Akustische und Kino-Gerate Gesellschaft in Vienna. The nominal polar characteristic of the microphone can be varied from omnidirectional through cardioid to a figure-of-eight by a multi-position remote control switch. Frequency response, sensitivity and noise have been measured on a single specimen for these three conditions.

The microphone has a wide frequency range. In the omnidirectional condition, the frequency characteristics are fairly smooth; in the cardioid condition, not only is the axial frequency characteristic very smooth but the variation in directional characteristic with frequency is less than is usual for this class of microphone. With a little equalisation at high frequencies the figure-of-eight condition would yield a nearly level response.