Surround : Surround Panning and Mixing : Divergence and Center Percentage : Divergence

Divergence
In the Panner Grid, the current divergence values are displayed using a purple outline.
By default, Pro Tools surround panners are 100% or fully divergent, meaning that a signal that is panned completely to one speaker will only be audible in that speaker.
Lower divergence settings result in a progressively wider source signal. When Divergence is less than 100%, tracks will be routed to neighboring speakers to some degree, even when the Pan Location cursor is positioned next to a single speaker.
To adjust divergence:
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