kinda practical lang po, i was given an audiovox head unit from a ford expi. I just notice it has no pre outs and i'm planning to put an amplifier para i-power yung 4 speakers sana and sub? Panu ko kaya gagawin to? kasi kung me pre out madali lang eh pero ito wala talaga, i need some inputs how to do it and what amplifier to buy kasi plano ko yung amps ang magpopower nung 4 speakers so 4 channels dapat? and concern ko papano yung sub? another ampli ba yun? meron bang amp na 4 channel tapos me pre-out pang sub? (newbie questions po). TIA.