KKmoon TPA3116D2 50W2+100W 2.1 Channel Digital Subwoofer Power Amplifier Board DC12V-24V Adopts two high quality TPA3116D2 digital amplifier chips. Sound quality is very good, high efficiency and amplifying power. 50W*2+100W 2.1 channels(left/right channel and subwoofer channel), high efficiency and low-heat. Powered by DC 12-24V, wide input voltage. User can adjust the volume by themselves easily. Applicable speaker impedance: 4-8 ohm.