You don't need a capacitor. I ran two 12's at 550 watts a piece and I never had any problems. Capacitors look cool and can shock the **** out of you, you do not need one. Spend the 50 bucks on something else.

 

With that low of power he doesnt need dual batteries.
Seriously op, if you have light dimming issues, upgrade your grounds. Google search "big 3 grounds" capacitors are a waste of money.

 

If you want to get technical capacitors are energy storage devices that tend to not allow for instantaneous changes in voltage.

They are energy storage devices intended to deliver (quickly) the energy that a subwoofer amp requires when the bass hits hard. They will not make your system louder, they help keep your voltage levels from fluctuating due to the large fast current spikes your amp creates.

If you have ever opened an amp there is a large bank of capacitors at the power stage of the amp for this exact purpose.

They can help save some life of alternator by not continuously drooping the voltage in your system and causing your voltage regulator to work overtime.

Electrolytic capacitors do fail catastrophically. So as usual you get what you pay for, but I would not let this deter you from their use. Main failure mode tends to be overvoltage or internal heating effects

Don't oversize your cap just to think it is going to help. Putting a 10uF cap in your system put strain on your alternator when charging

If your electrical system can't continuously deliver the energy that your system needs a cap isn't going to change that. (upgrade your wiring, good battery, etc)

^^ What he said, do your big three. The stock frame to ground cable is only like 8 or 10 gauge. Current in equals current out, so this wire has to carry all the current from your amp back to the battery. So using 4 ga wiring to your amp to the frame ends up getting restricted on its way back due to the stock wiring.

 

So I should basically just upgrade things first? I won't be running much really, but I thought a cap would save me from upgrading all my wiring and stuff. I just put a better battery in today, so that should make things better. The thing charges at almost 15v at low idle and cold. I can get some thicker ground wire if that would make things better. Upgrading the alternator would not be till later down the road. I think I'll only be using 8 or 10 gauge wiring just because I'm only pushing 500w. I imagine the Alpine amp will have some better components in it also. I'll talk it over with a friend of mine and see what he thinks. He could just get me a good deal and said it would be worth it in the long run. Especially since the other kit is gonna be one from wally world. I'm not sure how much that would last.

 

I have always used a 1 farad capacitor per every 1000 watts

 

I agree caps are a waste of money. your wattage isnt even enough to dull any lights. but even if they do. get a new battery

 

I've had several amps & subs in my vehicles over the years, ranging from 50 watts to 1,000 watts and never needed a cap.
Then again, I've never owned a Jeep before so..............

 

I have put together stereos in 3 of my friend's old trucks. All had at least 2x 12"s with massive wattage, all the bass tricks you see on youtube we could do with these trucks. Never used a capacitor. Hooked one up for the hell of it once and literally the only thing that happened was it got a little bit warm. No difference in sound or voltage drop confirmed with a DMM. Waste of money.

 

I'm staring to think twice about a cap then. I feel like most people say no to it.

 

DMM likely wont show a voltage drop.Transients are too fast. You would need a scope to see them.

If you have a cap don't be afraid to use it just don't invest a bunch of money on one thinking its the end all be all for increasing the performance of your system

 

I'm running 1700watts in my 99 cherokee and my battery that is 5 years old is working perfectly

 

Just get an Optima! I ran alot more than you are through mine and never had a problem.

 

Well the other night my interior lights started to dim when the bass hit on my normal speakers, haha. So I decided to go with a cap. I got a great deal on a cap and a complete wiring kit and hooked all up over the weekend. The bass hits hard and I have no dimming of anything it also seems like my headlights don't dim when the transmission downshifts like they used to.

 

I run an 1800watt amp to 2 twelves in a comp box. No cap and cranking at 14volts on the gauge.

 

Hey all. DortDizzle has some good info that should be listened to.

Also, I worked in a car stereo shop for several years, and have been under the hoods of cars all my life, and I'm currently an IT consultant. So I know a bit about electricity and electronic circuits. When I was doing systems, I generally recommended a 1/2 farad cap for each 500 watts of amplification.

FYI, when I was doing mods on my 98 after I bought it, some of the first things to go in, besides a brand new engine, were a new alternator, and 850 CCA battery. All grounds were refreshed. I have the Putco headlight harness with Autopal housings and Philips 9003 XPS2 X-treme bulbs.

I ordered all of my stereo stuff and started putting it in. The cap was originally back-ordered and took a week longer than all the other stuff to come in from Amazon. Anyway, I put all the other stuff in, and wired it up temporarily without the cap, but in a way that would be easy to integrate it once it came in. I used wiring adequate for the amperage draw I would have, and everything was running on dedicated circuits and fuses straight from the battery. No weak spots here.

I can assure you that at idle, even with just a Dual 400 W max amplifier running in bridged mode at about 2/3 gain, pushing a Kicker 6.5 inch sub, and the radio volume at 3/4 my headlights would flicker with the beat of harder bass notes. And I don't like any distractions when rocking Foo Fighters at a stop light. That first week drove me crazy. The next week once the cap came in and was installed my pulsing headlights went away.

For those of you that don't know, an amplifier doesn't pull a set amount of power (wattage) equally at all times. Low notes require more power. Loud notes require more power. Low AND loud notes require more power, but only while those notes (bass) hits, not between the hits. What the cap does is act as a reservoir to provide a surge of power when the amp needs to blast out those bass notes. Then, when the note is done, the cap "fills back up" for the next note. The ancillary effects are instant power to your amp when it needs it most, without having to pull it all the way from the battery through the wiring, and a more even load on the charging system as a whole.

Do you have to have it? No.

Will not having one shorten the life of your headlights? I can't say, but I would suspect that, much like household bulbs, headlights don't like frequent voltage fluctuations and surges either.

Will not having one damage your charging system? Maybe. It's a function of how much surge and how often.

Will your amp be "louder" or "hit harder" with one? Possibly. And if it does, it's just a dead give away that you were straining the electrical system to begin with.

Will not having one ruin your car stereo? No. Not if you have it wired up right.

The way I see it, the $30 or less it will costs you will do nothing but improve your system and address ancillary issues on the rest of the electrical system. It's cheap insurance. Just don't go bigger than you need. It won't do you any additional benefit, but can amplify (no pun intended) those very rare but sometimes catastrophic failures.

If you want more car stereo info, scan through some of my posts. I've put a ton of info out there for anyone who wants an education, wants to know what's really important vs. hype, and even some basics on 12 volt electrical that will prove useful even for non-stereo-related projects.