REAudio SA 1500.1 1800W Monoblock SA Series Class D Amplifier SA Series Monoblock Class D Car Amplifier RMS Power Rating: 4 ohms: 280 watts x 1 chan. / 2 ohms: 500 watts x 1 chan. / 1 ohms: 900 watts x 1 chan. Max power output: 1800 watts Mono channel operation Speaker-level (high-level) inputs with signal sensing for automatic turn-on