The SXE-3000.4D/BK is a 4-channel car amplifier from the DS18 SXE series, built as a Class D design. It delivers 2 x 500 watts RMS at 4 ohms, 4 x 320 watts RMS at 2 ohms and 4 x 200 watts RMS at 4 ohms. The channels are bridgeable, so you can combine them to drive a subwoofer or a pair of higher-power speakers from the same amplifier. Total harmonic distortion is rated at 0.05% with a signal-to-noise ratio of 90dB. A selectable HPF/FULL/LPF crossover covers 40HZ-2KHZ, so you can send each channel only the frequencies it should reproduce. Bass boost is adjustable from NO centered between N/A. Match the amplifier to the RMS rating of your speakers or subwoofers and set the gain to that rating for clean, reliable output. | Ds18 Audio | | SXE 4-Channel Class D Car Amplifier, 4 x 200W RMS at 4 Ohm | Black | Best Buy