I have no idea what they are used for... like this thing, its used for car stereos but i dunno what they do..

 

An amplifier uses a greater amount of voltage as the sound levels increase. Voltage is, by definition, the difference in potential energy measured between two locations.

So, a capacitor is a short-term "battery" that stores energy for when the amp's voltage and amperage needs are greater than what the car's electrical system can provide.

In this case, the "cap", as it's commonly referred to, lets your amp hit high notes and deep base without dimming your car's lights, or anything else like that.

 

would this also solve the problem if the amp cuts out a litle at high volume?

 

Capacitors are like small batteries. Ever unplug a radio from the wall and have it still play for couple of seonds? That's because the power supply charges the capacitors and the capacitors actually power the radio. When your stereo thumps, it pulls more juice than your car's electrical system can pump out. The capacitors can react faster so they make up the difference.

 

Depends... an amp can "clip" at high volumes if the amp is a piece of crap. If the whole range of music "dims" then you might need a capacitor. However, if only the high notes "clip", you might need another amp or better speakers... I'm not a stereo expert, so I can't say.

 

The "flux" capacitor allows you to travel in time

 

As long as you have 1.21 gigawatts of power!

 

Way to hijack a thread.

Well, this WAS productive.

 

AS everyone pointed out it is a energy storage device. The big ones are in the 1-farad range (or more). Its effectiveness can be huge if the wires getting to the amplifiers in the "back" of the car are a bit small (with some caveats). There is also the matter of different batteries -- different ones have different internal impedances and this has some bearing on "all of this".

For example, if you had a "perfect" battery, in the trunk feeding the amps, you could get away NOT using a big cap for "reserve" energy/peak energy needs. (I haven't seen a perfect battery yet -- they all have some amount of internal resistance that limits peak current flow.) One other topic that is not addressed is “some” batteries have internal noise mechanism that the capacitor will help to eliminate – with newer amps, this is not such an issue (for technical reasons).

However, in a lot of situations, a typical car with a BIG stereo (big hungry power amps) will need to be supplied with reserve (current) that the BIG cap (as pictured) supplied.

So, I know some of this sounds like techno-babble", but in the "right" circumstances, it will really help out with high power transients...

(It depends -- I will say that it probably wouldn't hurt...)

IMO -- if you like drums and "percussive" sounds at high volumes, it couldn't hurt...

 

Umm ... I think this is an amp related problem. I never had anything like this happened to me.

Regarding the cap., with 150Amp stock alternator, I dont think you would need a cap unless you have an 250watt (or higher) rms amp running at full load with all lights and accesories turned on.

 

Uhhmm it takes the voltage created by your alternator and transforms it to 1.1 gigawatts then sends you bak to the future !!!

 

i thought i was the only one that didn't know what it was.

 

hahah yea i was scared to ask, but i figure why not.

 

flux capacitors? haha, and i thought these replies would be from highly skilled electrical engineers or something. heh

yeah, you wouldn't need a cap unless your amp(s) are drawing too much current from the battery/alternator. The consequences from an amplifier sucking too much current would be like instrument panels and headlights dimming at random frequencies during music play. If this happens, a capacitor would be the solution.
Yes, you can think of it as a (very temporary) battery that drains by the millisecond. When you turn your car on, it would charge up again (called DC steady state) and kick in every time your alternator or battery can't provide the juice, so it can focus on headlights and other things. Installing one isn't hard either... just make sure its wired in parallel with your amps.

 

Ever wonder how an airbag deploys in a frontal impact when the battery is crushed? Capacitors!