Product description Prodcut description: Power supply: Dual DC±46---±60V(recommrnd Power: 1000W Efficiency: >=92% Signal to noise ratio: 88dB Input sensitivity: 1.5V (effective value) Input impedance: 3.3KΩ Frequency Response Range: 20Hz-20KHz Output speaker: 2-8Ω Voltage gain: 38 times Output short circuit protection: Yes Overload protection: Yes Overheat protection: Yes Overvoltage protection: Yes Zero-point protection: Yes Size (L * W * H): 12*5.9*2.27CM Note: 1. Standard voltage: ±46---±60V can work normally (more than ±60V, must burn, burn out will not pack). 2. The power supply is recommended to use a dual-supply power supply with a good power filter. 3. Before using electricity, please check carefully whether the wiring is correct and firm. 4. Speaker recommended: 10-20 inch 2 ohm~ 8 ohm speakers. 5. This board amplifier output voltage amplification is 38 times, if the output power is not enough, you need to add a preamplifier. 6. The lower the supply voltage, the greater the load resistance and the lower the total power. The bigger the other way around. Package Included: 1PC