Coincident Taping Methods

Coincident techniques are the most popular type for stereo recording. These are most often implemented using directional microphones vertically aligned on a common axis and set at an angle to each other in the horizontal plane.

The advantages this method offers are minimum phase differences between the two capsules for sound sources lying within the horizontal plane. Another is the angular accuracy of the stereo image not being affected by the distance of the microphones from the sound source. All large diaphragm (1 inch and larger) microphones should be used in this manner for satisfying results. Some small diaphragm microphones , most notably the Schoeps Collette series, suffer from a lack of "sense of space" utilizing this method, due to the lack of interchannel delay time. The Microtech Geffel small diaphragm mics do not exhibit this problem. Near coincident techniques are recommended for microphones with these problems, where they can yield very good results.

The microphone polar patterns used for this can be anything between the figure of eight to the subcardioid pattern. The angle between the center lines of the pickup patterns of the two microphones, or "included angle", is determined by the polar pattern of the microphone, the position of the sound source and the desired effect (i.e. how much room sound you want, the width of image and the like). For the smoothest , widest image, the included angle should be twice the value of the angle between the center line and the -3db point on the polar pattern at 1khz. Poor acoustic conditions could mandate a smaller included angle in order to reject undesirable components or a microphone with a tighter polar pattern.