Optional matching power supply:The power connector is a standard 5.5MM power , the same as most notebook power supplies. The power supply for the board is critical. The higher the voltage, the higher the current and the better the output power. If you only have 12V 1A, it can driver 3-4 inch subwoofer . If you are above 19V 5A, there is no problem driving the 8-10 inch subspeaker, and the power supply must be highly valued. Digital subwoofer power amplifier board with preamplifier op amp NE5532 buffer matching. The product uses the new US TI company TPA3116D2 high-performance power amplifier chip as the core, DC single power supply 8-25V wide working voltage, 50W (left channel) + 50W (right channel) two-channel output, the efficiency is up to 90%. Can use switching power supply, laptop switching power supply, battery or car power supply, etc... Power supply range: DC8-25V Number of channels: mono(Subwoofer output) Output power: 100W Turn the knob to the bottom to turn off the state Colour:Green Material:plastic Size:75X60MM Package Contents: 1 * Amplifier Board Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.