The GX-A604 is equipped with both low-level and high-level inputs, allowing conncetion to virtually any factory or aftermarket head unit. Low-level input is made via standard RCA connectors and high-level inputs made via a supplied Molex connector and harness. The 12dB per octave electronic crossover is fixed at 80Hz and can be selected either high-pass or low-pass. This allows the GX-A602 can be used as a an amplifeir to drive full-range speakers or as a subwoofer amplifier. The GX-A602 also has an switchable bass boost circuit on the rear channels that adds a fixed at 45Hz and will provide+12dB of gain.