Memphis Audio 16PRX5550 / 16-PRX5.550/16-PRX5.550 5 Channel Amplifier THD % (4): &lt;.05 Dimensions (in): 15.4 x 7.2 x 2 RMS 4 (Watts): 50 x 4 / 200 x 1 RMS 2 (Watts): 75 x 4 / 300 x 1 Frequency Response: 20Hz - 20kHz