kicker cx400.1 400 watt class d mono amplifier for car audio speakers, black kicker get the most out of your sound with the kicker cx400.1 amplifier for car audio speakers. cx-series mono amps are ohm stable, giving you even more power and wiring options for your system. a powerful 12 db crossover and 24 db subsonic filter are included, letting you quickly tune your system to perfection. use the full-range outputs to expand your system with other bass amps, or a full-range amp to complete your system. cx.1 amplifiers accept up to 40 volts of speaker-level input signal. this kind of flexibility makes line-out converters unnecessary and optimizes your sound quality.