1. TPA3118D2 high power amplifier board 2*30W 8 ohm 60W 4 ohm output, this board uses official standard circuit to open enough power and low heat, 32dB gain test2. When the volume is not plugged in, the volume is turned up to the maximum and the low noise is not heard.As long as the power supply does not interfere with the power amplifier board itself, there is no interference, as long as you connect the o cable. If there is no interference, then it is perfect.3. This circuit design uses the test application circuit of TPA311X chip instead of the official standard circuit, so please do not make any changes to the circuit of the component on the power amplifier board, so as to avoid unnecessary loss caused by overheating of the chip!Maximum Power Per Channel: 60WChannels: 3 (2.1)Product parameters:Power amplifier chip: TPA3118DD2Power supply: DC15-25VCurrent: 4A or moreOutput power: 30W 30W 60WOutput channel: 2.1 three channelsFrequency response range: 20-18.5KHzHarmonic distortion: THD-1%The power supply requirement is 15-25V 4A or above, 2 x 30W 8 ohm 60W 4 ohm can work normally.If only the power supply below 3A is used, the perfect one is 2 x 25W 8 ohm 50W 8 ohm.colour:Green blackMaterial:PCBsize:80 x 68mmPackage Contents:1 x Subwoofer amplifier boardOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is /- 1-3cm.