A power supply unit with the following specifications is recommended for the power supply of the BluBOX: 9 to 12 volts, direct current (DC), 300mA, center negative.

If a power supply unit with the wrong polarity (center positive) is used, the BluBOX may be damaged. A diode is built into the BluBOX anti-parallel to the supply voltage, which can prevent damage at least temporarily if the polarity is incorrect, but this is not a real protection against polarity reversal. In the long run, and especially when using more powerful power packs, a polarized power pack will sooner or later lead to a functional failure of the BluBOX.