DigiTech HARMONYMAN Owner's Manual page 12

Guided Tour - Rear Panel
4. Ground Lift
Eliminates most "hum" problems with having two guitars and amps
connected to the HarmonyMan
your amp, try pressing this button.
5. Main Outputs
Left only (mono) output, or stereo output. When stereo output is used, the
harmonies are hard panned left and right and the lead is panned center.
6. Power Supply Jack
Connect only the included PS-0913B power supply here.
6
. If you hear hum or buzz coming from
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