How do i know what capacitator i need?

How do i know what capacitator i need?

Have 500 watts now, want to add 300 more, what capacitor do i need, what price should i expect?

Depends how much money you want to waste.

To answer your question, it is a "general rule" to use .5F for 500W, 1F for 1000W, and so on and so forth.. 1F CAPS cost around $60 on eBay (digital readout) and around $40 (without digital readouts) There I answered your question

It is also a widely known fact that they don't offer any benefits in real world applications because of their very high ESR.

i'm not completely sure about this but i believe the ESR on a capacitor is much better than that of a battery.. The problem with capacitors is that they are rarely needed when people use them.. amplifiers have capacitors already to maintain voltage... a stiffening cap may help to a very small degree as far as keeping the voltage maintained as long as your electrical system is strong enough to handle your system in the first place.. most people, however, buy capacitors thinking that it will make up for a lacking electrical system and then the cap just becomes an extra strain on the electrical system because the caps energy must be recharged everytime it has dishcharged.. therefore if you are doing a burp (big hitting bass note) and you drain the capacitor, the voltage will drop across the amp as the cap is recharging. I dont think capacitors are completely useless, however i do not think they are necessary. I had a 2 farad capacitor for awhile and noticed almost no difference at all.. dimming was slightly less and voltage drops were minimally less with the cap.. barely noticeble, but slightly better.. If you want it i'll sell it to you for 30 bucks.. i paid 150. Has a voltmeter and everything on it.

subby, I know you post in CarSound... ever heard of the Richard Clark CAP challenge? -- $10,000 for anyone who can pass a blind test and correctly identify which setup HAS a CAP by just listening to it. Few people have tried, but no one has been successful.

with the formula .5 farad for 500 watts, is that RMS or Peak?

I have not heard of richard clark's Cap challenge..I havent been on that site in awhile, is that a new thing or is it really old. The amp challenge wasl the main hype while I was on that site.. . And i think he's been doing that for years.. its pretty contrary to what most people think, but looks like its true..

I wasnt recommending he get a cap just letting him know what my feelings were towards them.. which was basically that theres very little if any reason to get a cap.. you might get slightly less dimming but thats about the only difference from not having a cap.

What he said... Spend your money on an Optima battery and some good power wire...