Would a 150amp alt be enough to power a 1200watt sound system with an .5 farad cap? If not, how much of an alt do I need?

Thanks

 

If your main use for stereo is music while driving, then a 150 A is fine but I would use at least a 1 Farad cap if not more. A very rough rule of thumb is to take the total of the fuse raitings of all your amps and somewhere between 1/2 and 3/4 of that number will be the actual current draw with the system wide open (if your listening to music).

 

Yeah for a 1500 watt stereo system I would be using the 150 or 175 amp alt and two 1 farad caps (or in an ideal world if you had the money and room, six 1/2 farad caps).