1400 watts is probable the rated output of the amplifier not the amount it draws.Amplifiers take a small amount of current and amplify it up to create something just this side of distortion.The better quality the amp the less distortion. Some of your better quality amps will be fused at 20 amps and produce 500 watts of power and lesser quality amps fused the same may produce a couple thousand watts of power albeit with plenty of noise (distortion).Subwoofer amps usually gobble up the most power due to the low bass notes.Jason