JBL VTX Series - When to Use a Pull-Back

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VTX A8 | Rigging Manual
12.5 WHEN TO USE A PULL-BACK
The use of a pull-back is common when the center of gravity (CoG) of an array falls outside the footprint of the Array Frame. Typically,
long curved arrays with a large downtilt qualify for this condition. When this occurs, LAC displays an error to indicate that the array
frame alone cannot achieve the down angle needed for the design (Example 1 - No pull-back). Using a VTX A8 SB Suspension Bar as
a bottom frame will move the array CoG between the two suspension points, enabling almost any down angle to be achieved (Example
2 - With pull-back).
However, when using the motors for the two suspension points to adjust the array angle, the pick-point flexibility of the AF array frame
is not needed. Using a Suspension Bar at the top and another at the bottom yields the same outcome, while saving some weight and
cost (Example 3 - Two Suspension Bars).
Center of Gravity Suspension Points
Invalid CG Location
LAC Example 1 LAC Example 2
LAC Example 3
Center of Gravity Suspension Points
Center of Gravity Suspension Points