Rated power measured according to DIN 45500 up to 1% distortion factor in 13,5V

Zapco Studio 500

1 × 286 watts, channel 1 at 4 Ohm
2 × 286 watts, channel 1 + 2 at 4 Ohm with 13,4V supply voltage
Current consumption 69,4A
efficiency 61,4%

1 × 818 watts, channel 1 + 2 bridged at 4 Ohm with 13,3V supply voltage
Current consumption 114A
efficiency 54%

818 watts total power