KICKER KEY2004 200w 4-Channel Amplifier w/Auto-EQ/Processor) Smart Amp 47KEY2004

The KICKER KEY200.4 is a four-channel amplifier and audio processor in one chassis. Press the selector, let the included microphone listen to your system, and the internal DSP measures what your speakers are actually doing in the vehicle, then corrects it. A 40-band automatic equalizer fixes tonal problems and a 24dB/octave crossover sets the working range for each speaker. Tuning that normally takes an installer hours happens in minutes.

On the power side it puts out 50W x 4 into 4 ohms, which is a large step up from a factory head unit feeding stock speakers. Bi-amp mode, automatic time alignment, automatic level adjustment, automatic speaker size detection and a 60/80/120Hz high pass filter are all built in, and every one of them can be switched off if you prefer to set things by hand.

FIT2 (Fail-safe Integration Technology) lets it connect to nearly any stock or aftermarket radio using high level inputs from 250mV to 10V, with turn-on from a remote 12V signal or DC offset. It is also compatible with newer start-stop vehicles.

The chassis is under eight inches long and less than two inches tall, so it mounts behind the radio, under a seat or in the trunk. If the amplifier gets hot, power-management circuitry applies a near-inaudible limiter to peaks for milliseconds at a time rather than cutting out or blowing a fuse.