Don't let your crossover be the weak link in your car audio chain. AudioControl's 6XS 6-channel crossover uses a steep 24 dB per octave slope to separate your high and low frequencies, along with a built-in line driver that'll beef up the signal from an anemic receiver.

The 6XS crossover features front. rear, and subwoofer inputs, along with four sets of outputs: front high-pass, front low-pass, rear high-pass, and subwoofer. It comes preloaded with crossover modules that will work in a number of system configurations, but you can change the crossover point by buying another AudioControl module, or by modifying the modules installed in your 6XS. A built-in filter cleans up extreme subsonics in your signal so your amps and subs will play louder and cleaner.

Once connected, the 6XS's dash-mount remote control makes managing your subwoofer output level easy — just twist the knob when you want more bass. The LED glows brighter when you increase the signal, and dims when you dial it back. Balanced inputs reject noise caused by your vehicle's electrical system, but internal switching gives you other options for dealing with ground loops.