1.This is a DC-powered 12-24V power supply, using TI's TPA3116D2 high-performance digital power amplifier chip as the core, one to do parallel bridged bass channel power amplification output, one to do left and right channel power amplification output.support 100W (bass channel) + 50W (left channel) + 50W (right channel) three-channel output. 2.Support external audio input interface, with preamplifier, bass crossover processing; bass volume, bass frequency, left and right channel volume, treble, function control switch / total volume, 5 adjustment potentiometers. 3.Wide working voltage, energy-saving design, efficiency up to 90%. You can use a good performance switching power supply, laptop switching power supply, you can also use a charging bottle, or car power supply, etc... 4.The board is a finished board that has been soldered and tested. Connect the speaker box according to the picture, connect the appropriate power supply, connect to the Bluetooth audio device to play, or connect the sound source input correctly. The main Parameters: Size (L * W * H): 100 x 100 x 24mm, excluding potentiometer and socket projection Operating voltage range: DC 12-24V(current 3-4A, or 19-24V / 4-5A, such as high power requirements 20-24V / 8-9A above) Note that the DC no-load voltage should not be greater than 25.5V.