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

Sony XM-D400P5

1 × 320 watts, channel 1 at 4 Ohm
Current consumption 31,1A
efficiency 76,3%

1 × 528 watts, channel 1 at 2 Ohm
Current consumption 53,9A
efficiency 72,6%

528 watts total power

measured with 150 Hz because of fixed preset low-pass filter