Korg prologue Owner's Manual page 61

Button 8 (GLOBAL 8)
These parameters relate to the prologue's display and power settings.
Brightness
Adjusts the display brightness.
Continuous use of the prologue while the brightness is set to a high value
will have an adverse effect on the overall life of the display.
Auto Power Off
Using the Auto Power Off feature, the prologue can be set to automatically turn off
after approximately four hours have elapsed without any operation of the knobs,
switches, or keyboard, and without any input. Once this occurs, you will need to
turn the prologue on again manually.
Off: The Auto Power Off feature will be disabled.
On: The Auto Power Off feature is enabled. For details, refer to "Auto Power Off
Feature" (p.10).
[1...10]
[Off, On]
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