On the phasing of microphones

Correct phasing of microphones is most important when two or more microphones are connected simultaneously to a single transmission system. The phasing of all gradient and of some phase-shift microphones is reversed for rewardly arriving sound waves. In this paper the phase-frequency characteristics of most common microphones are described; methods for predicting or ascertaining the phasing of microphones are given; and a system is proposed for experimentally determining the absolute phasing of an unknown microphone.