Rated power measured according to DIN 45500 up to 1% distortion factor in 13,5V
Impulse SD-640
1 × 58 Watts       channel 1             at 4 Ohm 
2 × 56 Watts       channel 1 + 2       at 4 Ohm
4 × 51 Watts       channel 1 up to 4     at 4 Ohm
1 × 177 Watts    channel 1 + 2 bridged at 4 Ohm
2 × 154 Watts    channel 1 + 2 and 3 + 4 bridged at 4 Ohm
308 watts total power