Understanding MS Miking
To make a Middle Side (MS) recording, two microphones are positioned as closely together
as possible—usually on a stand or hung from the studio ceiling. One is a cardioid (or
omnidirectional) microphone that directly faces the sound source you want to record—in
a straight alignment. The other is a bidirectional microphone, with its axes pointing to
the left and right of the sound source at 90° angles. The cardioid microphone records the
middle signal to one side of a stereo recording. The bidirectional microphone records
the side signal to the other side of a stereo recording. MS recordings made in this way
can be decoded by the Direction Mixer.
When MS recordings are played back, the side signal is used twice:
• As recorded
• Panned hard left and phase reversed, panned hard right
MS is ideal for all situations where you need to retain absolute mono compatibility. The
advantage of MS recordings over XY recordings is that the stereo middle is positioned
on the main recording direction (on-axis) of the cardioid microphone. This means that
slight fluctuations in frequency response that occur off the on-axis—as is the case with
every microphone—are less troublesome, because the recording always retains mono
compatibility.