Why a Capacitor will never help your stereo...

[Mike Mayron]

Well I'm tired of hearing about people wasting money on them hoping to fix eletrical problems.
So here, read this and you'll never want one again, unless you don't finish reading it.

http://www.carsound.com/ubb/Archives...-000307-5.html

[Reverend_Ezekiel]

That was some VERY interesting reading.

But I'm still keeping my Capacitor. ;)

[v6maro]

[QUOTE]Originally posted by Mike Mayron:
Well I'm tired of hearing about people wasting money on them hoping to fix eletrical problems.
So here, read this and you'll never want one again, unless you don't finish reading it.

http://www.carsound.com/ubb/Archives...-000307-5.html[ /QUOTE]

well, if they dont work, then why have my lights stopped dimming? You buy the right kind, and it'll do what it says.
-Steve

[zccop2001]

let me clarifiy what a cap is mostly used for.

Alot of people know, a cap isnt guarenteed protection against killing your alternator. But it does allow the amp to run at peak power all the time.. Take it off, your lights dim like hell, but the cap (even thou your electical system is dimming) allows a concurrent flow of power, reguardless of the car. I personally experienced this many times, had the same setup in two cars.. both started w/o the cap, then i put it on, the difference in hard bass is where you see it, like 130+dbs, usually a electrical lag will restrict the amp to emit full power..

sound about right? i know it makes sense to me.

dave

[ToddBoe]

I do agree with the one or 2 capacitors really do not help a system that much they do some i do compotitions and i run either the alumapro 5 farad cap or the 15 farad depeind on the vehicle the one or two capaciters just delay the inevitable on the alternator dyeing is about it. For major spl the 15 is great and i got mine for about $400 which if you think aout it a normal capciter is 100 and so basically you get 11 free capaciters and thy only take up the space of about 3 caps or less in room. the 15 dose now the 5 farad takes up about as much room as 1 capaciter and it ran me about $300

[MTMike]

A cap is nothing more than an electrical reservoir. It doesn't increase the flow of current to the amp, but it gives it a reservoir to draw from when the alternator isn't putting out the current the amp needs. This will cause the lights to stop dimming, but it will not magicaly save your electrical system.

If you're running a really hefty stereo, put a high-current alternator in there and you won't need a cap at all.

Another option is a dual-battery setup... where you have one battery dedicated entirely to the stereo and the other is the car's main battery, and an isolaoter will keep them separate, yet keep them both charged. My dad engineers, designs builds and sells these setups.

-Mike

[Mike Mayron]

Geez, half of you guys didn't even read it. I can tell.

He clearly states that ohms law will not permit the cap to discharge and recharge faster than the amp can suck down the power itself because of it's ESR, and it will actually become a resistor and restrict curent to the amp. The only thing it is good for is keeping your lights from dimming.

From my experience, If you put enough caps in a car w/ a horrible wiring they might help on simple bass beats like in rap; but the only way to help get more power to your amp is w/ a better alternator or a second battery granted your wire is up to spec. I used to get voltage drops real bad untill I replaced the wire from the alt. to the batt. w/ some 4 Gauge.

On a side note, the new buzz is all about these http://www.batcap.net things than are like a cap but can dispence like 4000Amps for 5 seconds which would actually be good for SPL metering. They still suffer a higher than useable ESR though :(

P.S. to all the doubters and science haters :rolleyes: , do what you want, it's your cash and system. I'm just providing some important info to those who grasp electrical concepts.

[Reverend_Ezekiel]

<blockquote>quote:</font><hr> The only thing it is good for is keeping your lights from dimming. <hr></blockquote>

That is exactly why I bought it! It comes in very handy when driving at night. In this sense, the cap does what it is meant to do, stop the lights from dimming.

[96firebird311]

<blockquote>quote:</font><hr>Originally posted by zccop2001:
But it does allow the amp to run at peak power all the time.. <hr></blockquote>
I think i'm disagreeing here. Not ALL the time. The post stated for a brief (VERY BRIEF) second. Then the voltage in the cap drops to like 9 or 10 volts, but wait we have our lonely battery over here with 12.9 volts so it begins to help out. Now I'll admit I'm no expert in this region of car audio. It does put an extra load on the alt. and helps for only a brief second, but somehow it keeps your lights from dimming too. I don't know. But I do know the best solution to all electrical needs is a high output alt.!!

[ChameleonGreen]

Look, here's how it is:

In a system that is NOT pulling more current than the alternator can provide, a cap will help you. The reason lights dim is because it takes a milisecond for the voltage regulator to realize there's more draw on the alternator and another milisecond to tell the it to supply more power for the draw. In those 2 miliseconds the cap discharges, helps out the amp, keeps the lights from dimming, alternator makes power, amp is happy now, cap recharges. Repeat process.

In a system that is pulling MORE current than the alternator can provide, a cap WILL NOT help you.

Here's how you can tell if a cap will help you. Go out to your car at night and shine the headlights against a wall. Play some very bass heavy music. When the bass hits, the lights will dim:

If the lights return to full brightness BEFORE the heavy bass is over, a cap will probably help you.
If the lights stay dim during the entire note and only return to full brightness AFTER the bass if over, a cap probably won't help you. Save more cash, buy a new alternator.

[v6maro]

<blockquote>quote:</font><hr>Originally posted by ChameleonGreen:
Look, here's how it is:

In a system that is NOT pulling more current than the alternator can provide, a cap will help you. The reason lights dim is because it takes a milisecond for the voltage regulator to realize there's more draw on the alternator and another milisecond to tell the it to supply more power for the draw. In those 2 miliseconds the cap discharges, helps out the amp, keeps the lights from dimming, alternator makes power, amp is happy now, cap recharges. Repeat process.

In a system that is pulling MORE current than the alternator can provide, a cap WILL NOT help you.

Here's how you can tell if a cap will help you. Go out to your car at night and shine the headlights against a wall. Play some very bass heavy music. When the bass hits, the lights will dim:

If the lights return to full brightness BEFORE the heavy bass is over, a cap will probably help you.
If the lights stay dim during the entire note and only return to full brightness AFTER the bass if over, a cap probably won't help you. Save more cash, buy a new alternator.<hr></blockquote>

Totally wrong! Helped me! Mine used to totally dim, but they dont anymore.
-Steve

[DEE97GTP]

V6maro, how is that wrong? Think of a capacitor as an extra battery, it is not a generator. It doesn't create power. A capacitor resist voltage spikes or dips. For instance, if you have 0 volts on a capacitor and connect the battery, the capacitor voltage will not change instantaneously. It is will have to charge, the speed of that charge is based on the time constant of the circuit( resistance(ohms) * capacitance(farads). The size of the capacitor is directly associated with how much current it can provide before draining.

So what does this mean? When you have a voltage dip(like when the amp draws alot of current for a bass note) the capacitor will provide current to the circuit because it is wanting to resist the voltage dip.

Here is some more reading,

http://www.howstuffworks.com/capacitor.htm

EE101 is now dismissed.... :D

DEE

[MTMike]

<blockquote>quote:</font><hr>Originally posted by DEE97GTP:
Think of a capacitor as an extra battery, it is not a generator. It doesn't create power. A capacitor resist voltage spikes or dips. For instance, if you have 0 volts on a capacitor and connect the battery, the capacitor voltage will not change instantaneously. It is will have to charge, the speed of that charge is based on the time constant of the circuit( resistance(ohms) * capacitance(farads). The size of the capacitor is directly associated with how much current it can provide before draining.

So what does this mean? When you have a voltage dip(like when the amp draws alot of current for a bass note) the capacitor will provide current to the circuit because it is wanting to resist the voltage dip.

Here is some more reading,

http://www.howstuffworks.com/capacitor.htm

EE101 is now dismissed.... :D

DEE<hr></blockquote>

[img]graemlins/thumbsup.gif[/img] :D

[ChameleonGreen]

<blockquote>quote:</font><hr>Originally posted by v6maro:
Totally wrong! Helped me! Mine used to totally dim, but they dont anymore.
-Steve<hr></blockquote>

Well if you had read my whole post you will see that sometimes it helps, other times it's bad. Obviously you fall into the category of people who are not drawing more power than their alternator can provide.

<blockquote>quote:</font><hr>Think of a capacitor as an extra battery<hr></blockquote>

This is another incorrect statement. A capacitor is NOT a battery at all nor is it remotely like one. A battery creates power through chemical reactions. A capacitor actually stores an active electric charge within it's guts. Kind of like holding a lightning bolt until you need that charge. The rest of that paragraph is correct though.

[DrMilhouse]

can we escalate this to an argument and start throwing some flames yet? :D

Why shouldn't I have a cap in my car? I went with out it and then I got one... after I got one, I see less strain, better speaker response and almost no dimming.

that's with only a 1.2f cap. maybe it won't help the alternator but having gone through them before, I'm pretty sure that this one is getting less of a work over (or maybe it's because I grew up and don't listen as loud as long as I used to).

After reading your article, I still see no reason why actual proof in seeing the difference before and after why I would not want one.

Thanks for the lengthy post though. :D