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Chapter 7 Imaging processors 143
When you are working with MS signals:
•
Values of 1 or higher increase the level of the side signal, making it louder than the middle
signal.
•
At a value of 2, you hear only the side signal.
•
Direction knob and eld: Rotate to set the pan position for the middle—the center of the stereo
base—of the recorded stereo signal. When Direction is set to a value of 0, the midpoint of the
stereo base in a stereo recording is perfectly centered within the mix.
When you are working with LR signals:
•
At 90°, the center of the stereo base is panned hard left.
•
At −90°, the center of the stereo base is panned hard right.
•
Higher values move the center of the stereo base back toward the center of the stereo mix,
but this also has the eect of swapping the stereo sides of the recording. For example, at
values of either 180° or −180°, the center of the stereo base is dead center in the mix, but the
left and right sides of the recording are swapped.
When you are working with MS signals:
•
At 90°, the middle signal is panned hard left.
•
At −90°, the middle signal is panned hard right.
•
Higher values move the middle signal back toward the center of the stereo mix, but this also
has the eect of swapping the side signals of the recording. For example, at values of either
180° or −180°, the middle signal is dead center in the mix, but the left and right sides of the
side signal are swapped.
Stereo miking techniques
There are three commonly used stereo miking variations used in recording: AB, XY, and MS. A
stereo recording contains two channel signals.
AB and XY recordings both record left and right channel signals, but the middle signal is the
result of combining both channels.
MS recordings record a middle signal, but the left and right channels are decoded from the side
signal, which is the sum of both left and right channel signals.
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 eld.
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 o-center instruments. It is also unsuitable for mixing down to mono
because phase cancelations can occur between channels.