Royer Labs R-121 - Manual (Page 14)

Figure 2 - Typical M-S Miking Technique
In M-S recording, one mic faces sideways, one faces forward as shown in Figure 2, and they are
connected as shown in Figure 3. If the outputs of the two microphones are equal (or made equal
using gain controls), the stereo pickup will be similar to that of two microphones placed as a
Blumlein X-Y pair, delivering a wide stereo image.
As you reduce the level of the “side” microphone, the width of the stereo image will narrow
until, with the side microphone turned all the way down, you have just the “mid” mic panned
center for a mono pickup.
If the outputs of the “mid” and “side” microphones are recorded on separate tracks, the electrical
connections shown in Figure 3 can be made at the mixer outputs and the adjustment of the stereo
separation can be done during mixdown, rather than during the actual recording.
Figure 3
Typical M-S connection set-up
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