The dot in the surround field, the pan puck, represents the position of the sound source on that channel strip relative to the listening position (in the center of the surround field). Drag the pan puck to position the sound source and, therefore, determine the signal routing. Moving the puck toward a speaker icon increases the level sent to that output channel.
If the input format is mono or stereo, the surround field has a dark ring around the circular grid, showing a green line that can span from a dot to a full 360-degree circle. It corresponds to the position of the pan puck and shows the angle (the position in the 360-degree surround field) and the diversity. The diversity is 0 if the pan puck is placed directly at a speaker icon, which means the sound source is only routed to that speaker channel. When you move the puck toward the center, the outer ring expands, indicating to what other speaker channel the sound source is routed.
You can modify the movement of the blue dot with these functions:
Press and hold the Command key while moving the puck to lock the diversity value.
Press and hold the Control and Command keys while moving the puck to lock the angle value.
Option-click the green puck to reset the angle and diversity values.
Note: A Stereo channel strip shows two rings, one for the left channel (blue) and one for the right channel (green) of the sound source.
In addition to moving the pan puck, you can adjust the numeric values of the following parameters by dragging the field or double-clicking it and entering a numeric value. The position of the puck changes accordingly.
Angle: Change the circular position of the puck and, therefore, the position of the sound source in the surround field relative to the listening position.
Diversity: With a value of 0, the pan puck is positioned at the outer ring, routing the sound source only to that speaker channel (or two adjacent speakers). Increasing the value routes the sound source to more adjacent speakers indicated by the outer ring. The maximum value is 1, also called super mono, when a sound source is playing through all speakers.
Amount: If the format of the channel strip is surround, the Amount parameter is shown instead of the Diversity parameter. Increasing the number from its default 0.00 value (the unaltered surround signal) moves the puck toward a speaker (depending on the angle value), reducing the signal level of the opposite speaker channels.
Elevation: Adjust the position of the sound source between ear-level speaker channels (0°) and height speaker channels (90°). The parameter is only available if the current surround format has height speakers.
Note: You have to select the Spherical button to get a visual representation of the height position.
Spread: This parameter is only available if the format of the channel strip is stereo. It determines how wide the left and right channels are spread apart (similar to stereo width). A value of 0° folds both channels into mono; 90° would be a typical stereo spread between a left and right speaker. A maximum of 180° would put the stereo signal in the left mid and right mid channels with an angle of 0°. A negative value represents a left-right channel swap.
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