Powering your UAFX Pedals

Note: Power supply sold separately.

UAFX pedals require an isolated 9 volt DC, center negative, 2.1 x 5.5 mm barrel connector (same as standard Boss connectors) power supply that can provide the following current requirements.

  • Full-sized UAFX pedals (with two footswitches) require 400 mA (milliamps) of current.
  • Compact UAFX pedals (with a single footswitch) require 250 mA (milliamps) of current.

Each UAFX pedal must be connected to a separate power supply, or connected to an isolated power connection from a multi-output power supply. Connect the power supply to the 9VDC connector on the pedal’s rear panel. 

When you first connect your UAFX pedal to a power supply, the footswitch LED(s) or left selection switch LEDs cycle, showing that the pedal is starting up. The startup sequence takes about 15 seconds.

Except on Golden and Starlight, there is no signal through the pedal during startup or when pedal power is interrupted.

Note: On Golden and Starlight, when the pedal is unpowered and when it’s starting up, the signals are pure analog dry-through from input to output, without buffering or any other circuitry, via mechanical relays.

Important Power Notes 

  • Each UAFX pedal requires either 250 ma or 400 mA of current. Make sure your power supply can deliver the correct amount of current to the pedal for proper operation and performance.
  • An isolated supply provides power and grounding that is electrically separated, usually by means of a transformer for each connector. Some low-cost power supplies might have separate connectors, but might not provide true ground and power isolation, causing noise and ground loop hum. 
  • If your power supply has multiple outputs, make sure that each output provides true isolation, or that you connect your pedal to its own power supply.
  • It’s OK to connect a power supply that can deliver more than 400 mA. The pedal only draws the current it needs and will not be damaged if the supply is 9VDC.
  • If your power supply is not isolated, you might hear additional hum in the pedal signals. If the supply cannot provide the correct amount of current, the pedal might not operate properly, even if the LEDs and switches seem to be working. 
  • Daisy-chaining (running multiple pedals from one output of a power supply) is not supported.

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