The Dark Energy requires an AC supply (not DC). The supply has to deliver an AC voltage in the range from 12 to 15V and at least 400mA (valid for Dark Energy I and III) / 800mA (valid for Dark Energy II). If by mistake a DC supply is used nothing can be damaged but in this case only the Midi/USB interface will work.

The sound generation unit will not work in this case! DC jack plugs with 5.5 mm outer diameter and 2.1 to 2.5 mm inner diameter are suitable.

A typical symptom for a wrong supply (DC instead of AC) is that the LFO LEDs are permanently on but are not blinking.