Yesterday I just got a good sealed well sub box for 2 12's out of a camaro for $50. Anyway, I already have a JL Audio 500/1(500w RMS) monoblock amp and I plan to get 2 JL 12w6v2 's(400w RMS each, 800w max). My question is, with this setup will I need a capacitor, or will I need to upgrade my alt or battery? The battery is just a standard one but is fairly new.

 

You shouldn't have to upgrade much of anything for that to work fine. Good choice of products, all be it on the very pricey side. Also, you might want to consider a good deal more power for those two subs.

 

Well, I have a that amp and it runs fine since i got a new alternator. No issues with battery life. It's justa stock replacement alternator. You should be fine.

 

You should be fine, but the 'big three' can only help.

 

i would recommend a capacitor aka power cap. it helps cushion the effect the amp has on the charging system. it also get the power to the amp alot faster since it has a charge nearby. on my car, i have 4 10's 2 amps powering the subs, they definetly hit harder after i installed the power cap. even though your system is not too stressful, over time it can still weaken your alternator/battery. you don't have to go for the ones w/ the volt guage on them but it's convenient to have.

 

i would go with a .5 fared cap a good rule of thumb is 1 f for every 1,000 Wats or 1k Wat

 

Search for Caps. They are a wast of money. NO SYSTEM SHOULD NEED A CAP. They are at best Band-aids for a weak electrical system. If the electrical system up-to-snuff there is NO need for one. This has been disused and debated over and over again. Fact is they are just a Band-aids for a weak electrical system, the proper approach would be to correct the shot comings in the electrical system.

 

my electrical system was not weak and it helped a lot withe lights dimming but then again that was a 1,000 Wat system

 

If your lights where dimming your electrical system IS 'weak'.
If it was up to the task the lights wouldn't have dimmed.

 

new alternator and a Optima battery is weak

 

Was the new alt a stock replacement? It's output at idle? Pulley size? There is more to the electrical system then the alt. and battery anyway. Resistance from bad connection and the wire gage. "The big 3"....
Just the fact that the lights are dimming is proof of a short coming in the electrical system. You see the lights dim because the system voltage drops. The voltage is getting pulled down because the system isn't capable of supplying the current that all the electrical components are drawling. If the system could supply the needed current the voltage wouldn't drop. This is how we know there is a weak link in the system. Could be just one bad ground at the motor. Have you done the big 3?

 

i've got a "new" alternator, 1/0 gauge big 3, and optima yellow top, and get no dimming with over 3000 watts. the alternator being new makes no difference if it doesnt have the output.

 

Any cap in there 1meanGTA???

 

ha, no, i did the research before i spent the money, so i know caps are worthless.

 

I agree with the cap thing NEEDAZ. All it does is soften the blow to the electrical system so you don't notice the dimming as much. But you do still have the voltage drop regardless.
Think of a wave, if you are in 6 foot seas and the waves have a short period you'll get beat to death. But if you are in 6ft seas with a long period between waves it's not as noticeable. But it is the same drop and peak on both.
If you have a weak(stock) alternator you need to upgrade. Most of ours are only 85a max.
P.S. when you are shopping for alternators look at the idle output, and what rpm they put that out at. Most 200a alternators only put that out at about 5000rpm. Thats great if you're on the highway, but as you are puttin around town you're back to square one. You really want one that'll put out about 120a at idle and regulate themselves at higher rpm's. Check these out, i've used them on multiple occasions while competing http://www.prestolite.com/literature..._4800-4856.pdf

 

Good note on idle output but it should be noted that alternators spin a good deal faster than the engine so 1,000 engine rpm is closer to 3 or 4,000 for the alternator. Still a good point.

As for light dimmage with 1,000 watts, I'm sitting on about 2k worth of power and have yet to see my lights dim with a ‘stock’ charging system (fresh rebuild and the big 3). Then again I don't blast it at night because I don't want the noise ***** invading my town, because too many people have complained about the punk kids, limiting my system and telling me what I can and can't install.

I'm going to join the majority and say what others and myself have said before. If your charging system is up to snuff then you shouldn't have a need for caps. Upgrade your grounds (aka big 3) if you're having any kind of problems and go from there. This will fix 95% of the light dimmage issues out there.

 

z28z34man, I don't want you or any one to think we're trying to bet you up over this cap thing. We're just trying to get you to re-examine you're electrical systems. I think it will help. Are you familiar with the 'BIG 3"? Have you done it? What did you get for a new alternator? If it's a high output is the charge wire up-graded?

 

by big 3, we mean upgrading the wire from your negative battery terminal to your chassis, from the alternator to the positive terminal, and chassis to engine block/head. i also did negative terminal to head, but it isnt really necessary. i used 1/0 gauge for mine. heres a link if you would like more information.

http://www.caraudio.com/forum/showthread.php?t=124175

 

it wasn't a hi out put but it was the best oreillys had to offer i figured that would be plenty for only 1,000 WATS

the wiring was 4 gauge down to a 8 gauge at a distribution block at the back and 8 gauge to a good ground

i am not saying a cap is necessary i am saying a cap is a good idea if you want to be nice to your electrical system and extend the life of the alternator

also a cap filter out voltage spikes because there at a very high fr x sub c = 1/(2piefc)

 

But the whole argument is if you wouldn't even need a cap to "help" your alternator if the wiring was up to snuff.

 

my motto is you cant be to safe especially with a Monte Carlo 3.4 with the alternator under the engine

 

First line, The stock alt. is probably OK.
Second line, The big 3 refers to upgrading stock wiring under the hood, not the wiring back to the amp. Have you upgraded the stock wiring under the hood?
Third line, If the electrical system is sufficient it couldn't care less about if there is a cap there or not. It's not nice to it, it's not bad for it. It doesn't matter.
Fourth line, That would take a whole new thread.

 

Ok "no system should need a cap"...

Ive got a brand new 100amp alt, 4awg charge wire to the yellow top optima battery, 2awg wire back to a block then to my 3 amps (1200w/600w/100w) and let me tell you the lights will damn near shut right off when it hits some good notes! Definately needs a cap... (and i need some earplugs )

 

i've got a farad cap to sell ya 84z28350.
$50?

 

sonix are you flowing me every thread i am in you seam to show up

 

a 100 amp alternator, brand new or not, is not nearly enough to power any respectable system. i believe the stock alt is 105. i noticed you only did one part of the big 3. power needs not just a positive wire but a negative. you having a "big" 4 gauge wire (i use 1/0 all around) from your battery to alternator does no good if the grounds are not at least as big. you need to upgrade the wire from your battery to chassis and from the head to chassis. as far as i know the alternator is grounded to the engine.

id recommend at LEAST a 180 amp, if not a 200 or 250 for running 3 amps. if you really want to, go buy a cap, just be sure to post back here after installing it, and let everyone know it didnt do a damn thing for you, so others dont make the same mistake.

does noone notice that all of the people with years of audio experience on here all say caps are bogus? by experience i mean installing and tweaking a lot of systems. i've seen numerous people say "i need a cap," not listen to my advise, buy one, then say "man i should have listened to you, this is one expensive *** paperweight."

if you think you need earplugs, you ought to hear my setup....

 

Stock alt was 65amp!!

With the old tired alt the motor would barely stay running because the voltage would drop so low


As for the grounds, im not sure if its enough but their is a ground strap on each head and a 2awg ground cable from bat to frame. Also using a 2awg ground out back for the amps.

Im thinking of getting rid of my whole stereo system and start over cleaning it up and getting some small 12" or 10" subs to fit in the well, my heads hurtin from them big 15" JL pounding behind it all night, its time to get rid of it i think!

 

Even though that your amps rms is 500, if its maximum is atleast 1000 watts or over, yes you want to get a capacitor for your amp. If your battery is standard, yes you are going to want to get a high performance battery. If your alternator is working fine now, you will not need to upgrade it.

 

who the hell is this guy? whoever he is, dont listen to him. with the car running, basically all the power comes from the alternator, working or not, BRAND ****IN NEW OR NOT, its output it what matters. you do not need a cap for any system. like i said i have over 3000 watts rms in my car, no cap, no dimming problems whatsoever.

 

i sell car audio on the side, and to be honest capacitors are a waste of money, i got a high output alternator rated at 105 and i upgraded my wires to larger ones.

>>> just get some decent wires and you should be fine

 

Anything I say is just a '+1' and is redundant here, but yah, caps are a waste of $$.

I used to install car audio at Best Buy for a while, and we sold everyone on a cap stating that BS that it helps with dimming lights; so we could make more $$ of of ignorant customers.

Who knows? Maybe Best Buy is to blame for starting the 'caps are needed' problem!