High output alternator

[texases]

P=V X I, as always (power = volts X amps). At peak, a ‘1000 watt’ amp could draw 83 amps, but your ears would be bleeding. At 120 watts you’re at a more reasonable 10 amps, not accounting for inefficiency in the amp. So let’s say you need an additional 20 amps on average. Any 100 amp alternators available? That and the biggest battery you can fit might handle your setup.