About The Range Of A Controller's Change - Boss GX-100 Parameter Manual

CTL/EXP
When controlling the On/Off target with the expression pedal:
* The range that can be selected changes according to the target setting.
* When the "minimum" is set to a higher value than the "maximum," the change in the parameter is reversed.
* The values of settings can change if the target is changed after the "minimum" and "maximum" settings have been made. If
you've changed the target, be sure to recheck the "minimum" and "maximum" settings.

About the Range of a Controller's Change

This sets the operational range within which the value of the setting changes when an expression pedal or other controller that
changes the value consecutively is used as the source. If the controller is moved outside the operational range, the value does not
change, it stops at "minimum" or "maximum".
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