Coincidence microphone
A coincidence microphone (from Middle Latin coincidentia , `` the coincidence '') is a stereo microphone in which two directional microphone capsules are arranged very close to one another in a common microphone housing, so that in the low and medium frequency range no or only very small relative phase differences (phase differences) due to path differences inclined sound incidence between the two microphone channels.
Such coincidence microphones are intended for pure, mono-compatible intensity stereophony , so that when the two stereo signals are electrically added to form a mono signal, the cancellation or impairment of frequency parts is avoided. The two microphone capsules can be rotated relative to one another in their axis of reference in the axial angle , and they usually have variable directional characteristics in order to meet the requirements of different sound recording techniques.
Coincidence microphones generate a stereo impression with high localization sharpness of the sound events on the stereo basis with little reproduction of the spatial impression.
Types of coincidence microphones
- XY arrangement with an angle of 90–180 °, cardioid microphones
- Blumlein arrangement with an angle of 90 °, eight microphones
- MS arrangement consisting of a figure-eight and a spherical microphone one above the other
The SM 69 microphone from Georg Neumann , which is combined in a single housing, achieved a high level of awareness .
Most coincidence microphones of two individual are small diaphragm microphones assembled
literature
- Klaus Bertram: About dealing with stereo coincidence microphones . In: Telefunken Zeitschrift , 1965, p. 338
- W. Hoek, K. Wagner: Stereophony recording technology . Berlin 1970