10.6

157Logic Pro Effects
AB miking
In an AB recording, two microphones—commonly omnidirectional, but any polarity can
be used—are equally spaced from the center and pointed directly at the sound source.
Spacing between microphones is extremely important for the overall stereo width and
perceived positioning of instruments within the stereo field.
The AB technique is commonly used for recording one section of an orchestra, such as
the string section, or perhaps a small group of vocalists. It is also useful for recording
piano or acoustic guitar.
AB is not well suited to recording a full orchestra or group as it tends to smear the stereo
imaging/positioning of off-center instruments. It is also unsuitable for mixing down to
mono because phase cancelations can occur between channels.
XY miking
In an XY recording, two directional microphones are symmetrically angled from the center
of the stereo field. The right-hand microphone is aimed at a point between the left side
and the center of the sound source. The left-hand microphone is aimed at a point between
the right side and the center of the sound source. This results in a 45° to 60° off-axis
recording on each channel (or 90° to 120° between channels).
XY recordings tend to be balanced in both channels, with good positional information being
encoded. XY recording is commonly used for drum recording and is also suitable for larger
ensembles and many individual instruments.
Typically, XY recordings have a narrower sound field than AB recordings, so they can lack a
sense of perceived width when played back. XY recordings can be mixed down to mono.
MS miking
To make a Middle and Side (MS) recording, two microphones are positioned as closely
together as possible—usually placed 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.