Will i need a higher quality battery or alternator if i buy an audio system that puts about 1000rms?

I'd go ahead and upgrade the alternator. It's not just the head lights you need to be concerned with. You've got your heater in the winter and A/C in the summer that consumes a ton of power, ECM, ignition system, etc.

At approx 100 amp, that comes out to 1200 watt. So you are cutting it close. I just would not pump up the volume at night with the headlights on. good Luck...

If your total system power is 1000 watts RMS or more, you will need to: 1. Upgrade the alternator to a high output alternator 2. Upgrade to a heavy duty deep cycle battery 3. Upgrade the "Big 3" - that is to replace (or add to) the power wire between the battery and alternator, the ground from the battery to the chassis and the ground strap from the engine/tranny to the chassis with at least 2 AWG wire. Failure to do this will result in the early death of the alternator as it will eventually fail. Here is a guide that will calculate what size alternator and power wires you need http://www.datafilehost.com/download.php?file=6d26c621 You will need Microsoft Excel. If you don't have Excel, use this link http://www.box.net/shared/nkkw1dhk4g A second battery is never a good idea as it's an added strain on the alternator to charge two batteries AND supply power for the car. The ONLY time a second battery is useful is if the audio system is to be used with the car off. A capacitor is only good so far as the audio system isn't trying to pull too much from the electrical system. A cap doesn't provide more power, it's designed to 'stiffen' the voltage to the amp, nothing else. If the current isn't there, a cap won't help. The alternator must have at least 20% more amperage power than the entire vehicle and sound system combined for a cap to be of benefit which is ironically the same requirements for an amp to be efficient. See my site for more info http://spkrbox1.spaces.live.com