10.6

170Logic Pro Effects
Logic Pro Surround MultiMeter Goniometer mode
A goniometer helps you to judge the coherence of the stereo image and to determine
phase differences between the left and right channels. Phase problems are easily
spotted as trace cancelations along the center line (M—mid/mono).
The idea of the goniometer was born with the advent of early two-channel oscilloscopes.
To use such devices as goniometers, users would connect the left and the right stereo
channels to the X and Y inputs, while rotating the display by 45° to produce a useful
visualization of the signal stereo phase. The signal trace slowly fades to black, imitating
the retro glow of the tubes found in older goniometers, while also enhancing the readability
of the display.
Because the Surround MultiMeter Goniometer is dealing with multichannel signals, the
display is divided into multiple segments, as shown in the image. Each segment indicates
a speaker position. When the surround panner is moved in a channel strip, the indicator
changes accordingly. This indicates not only left and right channel coherence, but also
the front-to-rear coherence.
Goniometer parameters
• Goniometer button: Switch the main display to Goniometer mode.
• L–R, Ls–Rs buttons: Determine the channel pairs shown in the main display.
• Auto Gain knob and field: Set the amount of display compensation for low input levels.
You can set Auto Gain levels in 10% increments, or you can turn it off.
Note: To avoid confusion with the Auto Gain parameter found in other included
effects and processors (such as the compressors), Auto Gain is only used as a display
parameter in the meters. It increases display levels to enhance readability. It does not
change audio levels.
• Decay knob and field: Set the time it takes for the Goniometer trace to fade to black.