Hertz Audio HDP5 5-Channel Class D Amplifier HDP5 Hertz 5-Channel 950W Max D-Class Amplifier RMS Power Output @ 2 ohms: 100 W x 4 + 550 W x 1 RMS Power Output @ 4 ohms: 75 W x 4 + 380 W x1 THD: 0.08% Dimensions: 6.73 x 13.54 x 1.83