1. TPA3156 series subwoofer high-fidelity 2.1 power amplifier board, on-board Bluetooth 5.0 chip, supports the installation of AUX (audio input) and USB (playing U disk and card reader), and can also install IR (remote control function) and AD_KEY ( button control)! 2. USB can support all lossless format audio file playback (WAV FLAC APE WMA MP3, etc.) a variety of audio formats! 3. TPA3156D2 power amplifier board output power: 2*70W+140W4Ω, power supply is 24V10A. (Amplification gain is 36dB for subwoofer + 32dB for left and right channels) 4. The gain of the channel of the power amplifier board is 36dB. The output power is relatively large, please try to connect a subwoofer speaker with a size of 6.5 inches or more and 4 and below 140W! 5. The gain of the left and right channels is 32dB, and it can be connected to a 3-6.5 inch high and low frequency speaker power amplifier board within 8 ohms and 30W. The power supply requirements are 8-24V (8V can be turned on, not 8V power supply can reach 2*70+140W) 24V5A power supply above To achieve the best output value, ( who use power below 21V are not responsible for the output effect) please use a power supply above 24V5A! Specification: Product name: 2.1 channel bluetooth power amplifier board Power amplifier chip: TPA3156D2*2 Bluetooth version: 5.0 Amplifier channel: 2.1 three-channel Supply voltage: DC8V-24V Supply current: 3A-10A Output power: 2*70+140W Output Impedance: 4 ohm Amplification gain: 36db-32db Distortion ratio: -1% Product size: 96 x 40mm Wide voltage power supply: 8V-24V DC power supply (can not be connected to a former) Different voltage outputs different power: voltage X current = power (the conversion rate of this board is 90%) The digital power amplifier voltage activated output current parameters are