JL Audio HD600/4 Class D 600 Watt 4 Channel Full Dash Range Car Amplifier Description: Class D Four-Channel Full-Range Amplifier Patented Technology: Single Cycle Control Differential-Balanced Input Topology: 2 pairs of inputs On-board Crossover: State-variable, 12 dB/octave Butterworth or 24 dB/octave Linkwitz-Riley, Low-Pass or High-Pass for each pair of channels Min Copper Power / Ground Wire Gauge: 4 AWG wire