800 watts is more than a little bass. An 80 watt RMS amp would be more than ample for most applications. High power amps use switching power supplies to increase 13.6 volts to the higher voltages required to obtain those prodigious amounts of output power. So if the new amp draws an average of 10 amps or more, I wouldn't feel comfortable with an alternator rated less than 55 amps. But it's the battery that's really more important. Look into one of those new "spiral" wrapped plates dry cells. They don't have models for every car, but they are truly "state of the art" in battery technology. I designed high end car audio for a time in my carreer, and I can assure you that a high quality 100 watt amp is going to sound much better than a cheap 800 watt unit. Choose wisely. Tod

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