How does a capacitor work? (Car audio)?

T

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short answer is that it stores energy and stiffens the voltage drop when using a lot of power.

and here is my long answer to that...

A capacitor is only good so far as the audio system isn't trying to pull too much from the electrical system. A cap doesn't provide more power, it's designed to 'stiffen' the voltage to the amp, nothing esle. If the current isn't there, a cap won't help. The alternator must have at least 20% more amperage power than the entire vehicle and sound system combined for a cap to be of benefit which is ironically the same requirements for an amp to be efficient.

It's recommended for every 500 watts MAX you use a 0.5 Farad cap
Example: 1000 watts MAX - 1 Farad cap

A capacitor must be charged just before you supply power to it once installed.

It's best to install it as close to the amp as possible. You may need to get additional power and ground wire the same size you have now. Otherwise, cut the ground and power wire leaving enough room to mount it. The overall length of the ground wire should as short as possible (18" or less if possible, not critical).

Remove the fuse at the battery. If you don't have one, you need one that is rated the same as the total fuses that are on the amp. It must be no more than 18" from the battery. This fuse is really just to protect the battery (and the car from catching fire) from shorts in the power wire, nothing else.

Connect the ground from the chassis to the cap then to the amp.

Connect the the power wire (from fuse by the battery) to the cap then to the amp.

To charge the cap, get a 12v light bulb with leads. Temporarily connect the power wire from the battery to one side of the bulb (at the fuse) and connect the other side of the bulb to the wire going to the cap. The bulb will light and over a period of time (10-20 seconds) it will get dimmer. When the bulb goes out, the cap is charged. Basically, your going to put the light bulb where the fuse was.

Now you can re-install the fuse and your done.

and remember to be careful with the cap as they can be dangerous if you don't do something right. always remove the fuse before messing with it
 
How does a car audio capacitor for a car work? Or just a capacitor in general i researched it and i didn't really understand it.

Also how do you wire two capacitors to a car? With 1 amp?
 
capacitor is a reserve of power, or a power conditioner, it keeps a constant charge should the amp require more power after the subs hit. it should be wired inline with the amp, also prior to installing the cap needs to be charged read the instructions carefully as you can damage the cap if done incorrectly. 1 farad per 1000 watts.
 
a capacitor stores an electrical charge and when contact is made is dischagres.. I own't get into the coils and electromagnetism etc...
so your sub question about wiring them to a car isn't detailed enough. the car frame? Why to shick someone that touches it? the car has 1 amp? you want a 1 amp capacitor? BTW amperage is what causes death, not the voltage, and a full 1 ohm cap WILL cause death if fully charged.. You should do some more googling.. remember that e= I X R
 
Take a seat. lol Get comfy.
The big caps for car audio power & the small ones in electronics do the same thing. They act as a buffer for current. They also smooth out any spikes in ac voltage. Looking at an oscilliscope the row of spikes at the top of the sine wave is called ripple voltage. Ripple voltage is crappy when you're trying to get dc voltage (which is the only usable stuff) from ac voltage (which can travel wayyyy farther than dc). And now you'll probably never hear about ripple voltage again lol. Caps are also used in speaker crossovers, but you're not asking about that use.
When a car is running, the alternator supplies current for everything, but not all at once or else the 100 amps would fry everything. That's why alt's use a voltage regulator. When the demand comes for current, the voltage in your car dips a bit, so the voltage regulator ups the voltage, thus upping the current that is supplied. I think the ppl that say caps have no use haven't considered how the voltage regulator works. Maybe they think the max amperage comes gushing out all nice & steady from every alternator. Or don't realize alternators have them and are just staying on the dont-use-caps bandwagon.
When an amp needs power to play a big bass note (which is why people consider buying caps), that amp is GOING to get it's power from somewhere. It steals the power from the other electronics in the car and that's why lights dim on cars when a loud bass note hits. The alt's voltage regulator will help for this by bringing the voltage back up, but it doesn't switch it up very fast, but these caps are lightning fast with enough voltage(pressure) going through them. So contrary to the people that say these caps are made to "stiffen" voltage, and nothing else, buffering current like this for bass is the big reason these big caps were put on the market. And when used correctly, they work great!
The correct way is to have approx. 1 Farad per 1000 watts rms of the amp it's hooked to. Also it needs to be fed plenty of power. It charges & discharges so fast it needs an alt with a lot of amperage that won't strain by charging the cap as well as powering all the other electronics in the car. And of course thick enough wire to carry the current.
You can wire 2 caps to one amp by wiring the caps in parallel. This adds the capacitance of the 2 caps together. The cap terminals can be hooked up to the amp in the same way you would hook a battery to the amp.
In general, a cap stores current. In smaller electronics, when you turn something off that has an led, for example, the led might slowly go out. This is one of those small capacitors discharging its stored current. Also, sometimes at home there will be a voltage dip on your mains, but your tv or whatever stays on. Well those little caps happen to be storing current, which is why the tv can stay on a voltage dip. Just like in a car, the amp stays powered up even thru a voltage dip.
 
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