SMAKN&Acirc; TPA3116 Amplifier Board(50W+50W) D Class Amplifier Board Board size 50 (width) X 75 (depth) X 29 (high) mm (not including projection potentiometer 15mm), Operating voltage range : 8 - 25V (supply current greater than 3A, 4A power to a large current or more) (Note: The voltage not more than 25V), Speaker impedance : 4 - 8 ohms, parallel bridged mono: 2-4 Europe, Maximum output power : 50W / 4 ohms (left channel) + 50W / 4 ohms (right channel), Output power: Tip: To the audio input in sufficient supply voltage / current enough, will have enough output power. Higher relative power supply voltage will be bigger, different speakers have different impedance output power. Under voltage and current enough, the number of speakers in Europe, the smaller the relative sound power, please pay attention! Power supply voltage: 12V ------- 8-European speakers / 12W (left channel) + 12W (right channel) 4 ohm speaker / 20 (left channel) + 20W (left channel), 15V ------- 8 Europe / 18 + 18W, 4 Euro / greater than 30 + 30W, 19V ------- 8 Europe / 32 + 32W, 4 Euro / greater than 45 + 45W, 24V ------- 8 Europe / 38 + 38W, 4 Euro / greater than 55 + 55W,