The amplifier board adopts two high quality TPA3116D2 digital amplifier chips as the core?↓ one ad left and right channel power amplifier?↓ the other as pre-bridge driver with NE5532 subwoofer?↓ which makes it features small size?↓ high efficiency and high power.Features: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.Just connect the power supply and loudspeaker box?↓ enjoy the pure digital music!Notice:This amplifier board must be powered by DC power(DC12-24V)?↓ it's better to use high-performance switch power. Don't use transformer!Specifications:Supply Voltage: DC 12-24VChip: TPA3116*2Channel Type: 3 Channels(Left Channel?↓ Right Channel?↓ Subwoofer)Output Power: 50W*2 + 100W*1 SubwooferOutput Match: 4-8 ohmAudio Output: TerminalsFrequency Response Range: 14-100KHzSNR: 100dBSwitching Frequency: 1.2MHzPCB Board Size: 100 * 70 * 30mm / 3.94 * 2.75 * 1.18in (L * W * H)Weight: 113g / 3.98ozPackage Size: 13.5 * 11 * 5cm / 5.31 * 4.33 * 1.97in (L * W * H)Package Weight: 167g / 5.9oz Package List:1 * 2.1 Channel Audio Amplifier Board1 * Audio Cable"