Ok a capacitor is a storage device, it stores power so when you get a heavy bass note from your stereo the amps draw a large amount of current, the capacitor supplies some of this current rather than directly off the battery. The advantage of a capacitor is that it prevents some voltage drop. by preventing voltage drop, you get better bass quality and also more bass not only from the woofers but also your speakers as it prevents other amps from dropping voltage as well. Amplifiers run better at higher voltages. People dont seem to understand that when large power is drawn from a supply voltage that is unregulate ie: a car. The voltage drops and the current increases.
You can have all the power connected to your amps and capacitors, just have the main fuse removed. The reason why u charge a capacitor is because if you didnt charge it and connected it to the battery, the split second it is connected the capacitor would draw a large amount of current quickly thus producing a spark and a cracking noise at the point of connection. It will scorch the battery terminal and the terminal on the wire. Almost like a split second arch weld. And also it creates a safety hazard to the fingers you are using to connect the wire. You use a resitor or a light bulb to reduce the voltage to the capacitor thus safely charging without the snap crackle and pop. If using a light bulb you will see the light intensity rise and then slowly go down again. As soon as the light globe starts to reduce it light intensity the capacitor is fully charged.
why not just save the effort and take it back to the store and get your money back. capacitors do nothing for an audio system they are a waste of money. in fact they have been shown to have a negative effect on a system. so long as you have adequate size power cables and good earths you will be fine.
Your comment is really ill informed, Try educating yourself on understanding electrical theory. They cannot have an adverse affect on a car audio system. They are not a waste of money.
It doesnt matter how manny capacitors or alternators u use, you will still get lights dimming with heavy bass notes because you are running your stereo off an unregulated power supply. Adding capacitors and or upgrading alternators will reduce the amount of light dimming.