DS18 SXE-4000.4D Class D 4-Channel Full-Range Car Amplifier 275 x 4 RMS @4 OHM 4000 Watts DS18’s SXE series of amps was designed for users looking for an extreme increase to the quality of music reproduced by their vehicle. The SXE-4000.4D guarantees your sound system’s speakers perform at their peaks on every use. The SXE series of amplifier gives users the ability to tailor the audio reproduced by their vehicle to their personal listening preferences through the use of it’s fully variable crossover, adjustable gain input sensitivity, and multi-channel amplifier design: everything you need to take control of your listening experience