Bumpin Balt

Here's some in depth info I found regarding the fact that capacitors are apparently useless for car stereo applications. http://forum.realmofexcursion.com/sh...ad.php?t=17970 ***IMPORTANT***: please read this entire thread before you decide what you believe!

disposable_her0

i dont have to read this...i have a kicker 5 channel amp that puts out about 1k watts rms...my lights dimmed when it hit hard. i bought a 5 farad cap and they stopped...so they work. i used to work at Circuit City in the roadshop and just about everyone that did work there had one because they had more than one amp

Broke EF

Caps dont do ****, I know people with cometition cars with no caps at all.

Sean

Bumpin Balt

I didn't want to believe it either, but this article provides hard facts and testing that prove them to be ineffective or even detrimental to a car stereo system because they put added strain on your charging system (alternator) and further limit the amount of power available to your sound system. If you can give me hard facts and testing to prove otherwise, I'm all ears (eyes?) because I was considering adding a larger cap to my system to support a third amp that I just added. From what I've read, your better off to invest in heavier gauge power wires and/or upgrade your alternator. Upgrading your battery is not necessary unless your going to use your system while parked.

disposable_her0

ok the reason lights dim on a cobalt is because the battery is in the back of the car so the power has to travel the full length of the car. a high out put alt can cost 200 or 300 bucks. the power kit i have is a kicker 0/1 gauge...so yea. it wasn't a bad dim i just didn't like it at all. besides people have been using caps for years and i have never heard of anyone having problems.

redSSBalt

Speaking as an ex installer for many years at a custom audio & security shop that held the world record at one point. Caps do in fact work if you are only using one battery. If you have more than one battery, than you really don't need a cap. If you are using more than one battery, you should really be using deep cycle batteries as well.

Bumpin Balt

I need proof that they work! Give me a link to a test study that proves they work.

EmperorJJ1

iTrader: (5)

hey rev i understand your new found knowledge and the fact that you want to share it with everybody but going off what you said about hard facts and all id would like you to show me a serious audio competitor with only one battery (unless limited by db drag)

A cap does work but few people use it for its intended purpose and those who could use it to its full potential usually dont because they already have upgraded to the point where its cost outways the benifits

Mnatvyc1223

hows about this, almost every circuit in the world contains capacitors, and believe me they range from small to huge as ***, for you car to operate properly there are various sizes and ranges of capacitors installed on the electrical systems in your car, do they work yes, people who say they dont have to be somewhat retarded it's just like sayin resistors dont work... <--------(ELECTRICIAN)

go study electronics and then come tell me capacitors dont work.... slap yourself...

cincybalt

not true.. . in my sentra my lights dim and the battery is in the front. it doesnt have to do with the distance power has to travel.. its the watt output.

Bumpin Balt

A serious audio competitor would have more than 1 battery because he needs to be able to get the most out of his system while PARKED! I said in my earlier post, "you don't need to upgrade your battery unless you want to use your system while parked". I didn't say it was a bad idea to upgrade your battery, it just makes more sense to upgrade your alternator first because it is the primary source of power for your sound system. While driving, your system only draws power from your battery if your alternator can't deliver enough current. In this case, your battery voltage is going to drop severely and your system is going to suffer. This means you need to upgrade your alternator because even the best battery is not going to help your system because your charging system is to weak to keep the battery charged, even while driving. I'm not trying to be a smart ass! Like most people, I'm here to learn and pass on the things I learn!

EmperorJJ1

iTrader: (5)

Well ill explain what a cap is and what it does and from there you can decide as you will.

A cap is made to be sort of a voltage regulator. It supplies current only when needed once the voltage drops and it does this very very fast. So depending on how severe the voltage drop the cap can be completely discharged within a second or 2.... So a cap cannot be used to remedy a electrical system that is failing but it can and will work surprisingly well on one that is either decent or good. The reason why caps have a bad rep is becuase most people that will use one have a bad electrical system. Using a cap on a bad electrical system doesnt work because the cap never has a chance to recharge since the amp and other componants are constantly needing more current. In that situation adding a cap only takes away from the charging system. Also when you install a cap you must charge it first using resistor that shoudl be included with all caps but usually isnt on the cheap brands. So people will just hook it up like normal and risk messing up the cap.

About the whole battery thing. I know your just taking the theory you read on that page and treating it like fact but a good battery alone can supply a ton of current. You can and some people do run the car off of what is bassiclly just the battery (system voltage stays at or around 12v all the time) for some time before running into problems. The reason it can do this is because even thou the battery is supplying power so is the alternator. two is always better then one and to go from 12v with both the alt and battery power to 11v takes quite a bit of current draw (if you ever see a sorta big system with a volt meter it will sometimes go below the 12v range but it pops back up to at least 12v almost instantaniously) This is why people can and do just upgrade the battery to an optima or comparable deep cycle battery and never get any type of dimming. 95% of people with a system dont have a upgraded alt and most can last just fine without one. Ive even seen a car with a wall of 4 18" subs run of a stock honda alt hit a 159 on the term lab meter and drive home just fine. In that situation the alt is going to eventually fail but with a serious battery bank (he had 6 of the big telecommunications batteries) you can run a system like that just fine

Bumpin Balt

If your alternator is cranking, your stereo will not draw power from the battery unless the alternator can't supply enough current to your stereo, either because your not using heavy enough wire or the alternator simply can't produce enough amperage to support the stereo. Then and only then will your stereo draw power from your battery. In this situation your stereo is not going to perform well for very long because the alternator will not be able to charge the battery quickly enough.

Omega_5

Wow... tha is just about the dumbest thing I've ever read....
Why do some guys get into these discussions? Why do they think they are electrical engineers?

Caps in series don't do ****! So really, what that guys says is true...
BUT! Caps in parallel are just like having another high discharge battery right at the amp. In cars with front batteries this is especially good! And because it's parallel, there is no voltage drop either!
Another positive, being a capacitor, it does the good old job of what a cap is usually used for... correcting voltage spikes! That's right... when you've pounded that little spinning **** box of an alternator into the ground and it has no voltage regulating capabilities anymore, that cap is gonna save some very sensitive components from over voltage in most situations.

If there is one thing I've learned about stereo's it this; pro installers know lots about the subs and speakers and amps and sound... but know jack **** about the power side of things before the amps and subs and stuff.

Edit: And don't get me wrong here... a good alternator, battery and power cable system is equally as important to a system.

EmperorJJ1

iTrader: (5)

your beating this into the ground here... i know well what a alt does but i was talking about specificlly caps and batteries. In my situation the stereo is limited but it can last... its all about current draw and how your alt charges... I recently had a spl comp and out of all the cars the shop i wnet with took i had the highest voltage when i ran... i bumped it once then did the comp vs everyone else playing it for some time. Does that mean my electrical is better then everyone elses? not nessicarily. Just think outside of the box for half of a second and realize it has alot of variables

Bumpin Balt

Point taken! I have decided not to believe the propaganda this "expert" is trying to spread. I have experienced first hand the benefits of adding a cap to a stereo system (no more dimming lights and tighter, louder bass!), so I don't know why I was so quick to believe this guy! I guess it was all the big words and "tests" he did. I don't think this debate is going to die anytime soon though! For those of us who believe in real world RESULTS, we won't lose any more sleep over this topic!

lOwBaLt

I use a cap, stops my light dimming. and its 2 farad....

Cap's dont work good unless its more than 5 farad in cars like hondas, pickups, suv's, etc (where they have the battery in the front)

but IMO for cars like cobalt (where the battery is in the trunk), just needs a cap. to stop light dimming, and etc. ofcourse I do have a Optima yellow top battery (might help it a lil)

college88

Reading all this stuff about caps and what not has made me question of the system in my car... i have a system that consists of a sony head unit, two MTX T45 12inch subs, and a sony 1000watt amp... would i need to connect a capacitor to it or no? t.i.a.

HatedCobalt

Caps, are usefull in "smaller systems" street beat cars with dimming headlights. A cap, adds resistance to your system which doesn't help a "comp" car.
This is my buddy's 1994 Ford Escort





That's the box he is currently working on. For two mojo 15's and 8 2500 watt Orion amps as well as 8 16volt batteries.



Nope you should be all set, if you headlights start dimming either A turn down the gain on the amp, or simply add a cap. nothing major.

kingg5

iTrader: (1)

common sense tells u they work.

HatedCobalt

I'll define what a capacitor is, how it works, and what it does. This is best done by the following webpage:
www.bcae1.com/capacitr.htm

Now with that out of the way, I'll give my take on what a capacitor will or will not do for you.

A capacitor WILL:
-Stiffen voltage rails. If you experience very brief, momentary periods of high current demand that cause the electrical system to falter only at these rare, peak draw times, then a capacitor will supply the additional current needed (when bass hits) to keep your voltage rails stiff, and prevent damage to the car or audio equipment.
-Increase response times for musical accuracy by reducing delay caused by transient response times between current demands from the amplifier, and response to this by the electrical system. In other words, your subs will respond more quickly, because they don't have to wait for the alternator to supply additional current at the moment of demand. Amplifiers have to provide a very dynamic and quick response many times. A capacitor can assist in this if the rest of the charging system is up to par.

A capacitor will NOT:
-replace the need for a larger, high-output alternator and/or a deep-cycle battery or batteries.
If your electrical system is inadequate, the ONLY way to fix this, and again I repeat, the ONLY WAY to fix this, is to replace the alternator. This is the SOLE source of electrical current for your car when the motor is running.
When the motor is turned off, the battery then becomes your source of electricity.
When the battery is run down, and when the capacitor(s) is/are depleted, the alternator has to work even harder in order to supply current to the car, the audio system, and also to recharge the capacitor(s) (which deplete very quickly) as well as recharge the car's battery(ies).
So by adding a capacitor to try taking the place of a high-output alternator, you are actually causing more work for your alternator, and causing even more damage to that stock alternator.
-make your system magically sound 10 times better.

Many people believe that a capacitor adds NO real benefit to an audio system, and this is why you never see before and after demonstrations, or factory capacitor company vehicles at competition events.
A capacitor does have it's uses, but it is not a magical fix for a lacking electrical system.

To calculate the capacitance needed for your system, you will need to find the peak or max power ratings of your amplifiers, and add those together. This is the only time peak amplifier power ratings are even remotely useful, since a capacitor is only used to cover very brief peak demands, and not cover for the continuous amplifier demands.
Take the peak power total and figure 1 farad of capacitance for every 1000 watts of power.

Capacitor:
A capacitor is an electronic device which consists of two plates (electrically conductive material) separated by an insulator. The capacitor's value (its 'capacitance') is largely determined by the total surface area of the plates and the distance between the plates (determined by the insulator's thickness). A capacitor's value is commonly referred to in microfarads, one millionth of a farad. It is expressed in micro farads because the farad is such a large amount of capacitance that it would be impractical to use in most situations.
Capacitor and DC voltage:
When a DC voltage source is applied to a capacitor there is an initial surge of current, when the voltage across the terminals of the capacitor is equal to the applied voltage, the current flow stops. When the current stops flowing from the power supply to the capacitor, the capacitor is 'charged'. If the DC source is removed from the capacitor, the capacitor will retain a voltage across its terminals (it will remain charged). The capacitor can be discharged by touching the capacitor's external leads together. When using very large capacitors (1/2 farad or more) in your car, the capacitor partially discharges into the amplifier's power supply when the voltage from the alternator or battery starts to fall. Keep in mind that the discharge is only for a fraction of a second. The capacitor can not act like a battery. It only serves to fill in what would otherwise be very small dips in the supply voltage.
ESR:
ESR is the equivalent series resistance of a capacitor. An ideal capacitor would have only capacitance. As you remember, all conductors have resistance. In a capacitor, there are multiple conductors like the wire leads, the foil and the electrolyte. The resistance of all of the conductors contribute to the capacitor's series resistance. It's essentially the same as having a resistor in series with an ideal capacitor. Capacitors with relatively high ESR will have less ability to pass current from its plates to the external circuit (to the amplifiers in the case of stiffening capacitors in car audio). Low ESR is desirable when using a capacitor as a filter.

ESL:
ESL is the equivalent series inductance of a capacitor. Since most electrolytic capacitors are basically a large coil of flat wire, it will have even more inductance than it would have if it were flat. This inductance, along with the small amount of inductance from the wire leads, will make up the ESL of the capacitor. The ESL is essentially the same as having an inductor in series with an ideal capacitor. Low ESL is desirable when using capacitors for filtering purposes.

Leakage:
Even though a capacitor's plates are insulated from each other, there is a small amount of 'leakage' current between its plates. This current is generally insignificant but will cause a capacitor to slowly discharge with no external circuit path between the capacitor's leads.

Note:
Some large capacitors used in car audio systems have a digital voltmeter on them. Some of these displays will have a remote turn on lead to turn on the LED display. Others will have a timer that will turn the display off after a few minutes. If, in either case, the capacitor's positive lead was removed from the power source (and the display remained on), the capacitor would be quickly discharged by the display. This is not the same as the leakage current that we previously discussed.
cited from:
http://www.bcae1.com/capacitr.htm
http://www.wickedcases.com/caraudio/capacitors.html

do the big 3: Add a 4 guage or lower wire:
1. From your battery ground to the chassis
2. From your alternator case to the chassis
3. From your alternator positive to your battery positive

EmperorJJ1

iTrader: (5)

i recognize the external regulator for the alt... is it an ohio gen?

HViper

Caps do work well when used in the right aplications, and so do extra batteries. I am only running one amp, but it is a power hungry one. It is a Fosgate power series mono amp that produces 1050watts RMS and peaks at 1800 watts. I thought about going with a cap for this, but then I heard about these badass batteries that are designed for car stereos. I am running one of these batteries and have no problems at all with lights dimming and such, and I do not have to worry about putting addtional strain on my altenator. This is more so preventative so I will not have problems, but I do believe that this amp would of killed my altinator over time. Here is the link to the websites for the company that makes these batteries, and IMO they are way better than any amount of caps on the market.

There home page; http://www.kinetikaudio.com/default.asp
The model I have is the Kinetik HC600 Power Cell "The Cap Killer" which is plenty for my aplication. They do have bigger models for other aplications, but this one is equal to 100 1 farid caps. Here is the direct link to the model I have in my car; http://www.kinetikaudio.com/hc600.asp

EmperorJJ1

iTrader: (5)

lol im using that amps big brother the T30001bd

My06Kobalt

Agreed. I'm running four 12" Infinity's and I got a 5 farad cap.