Multi-farad Capacitors - Noob Question

[Deacon]

Hey gang,
I was hoping someone would clue me into these big capacitors I see in audio and CB shops. What are they used for? Would anyone mind providing me a little bit of detail on what the purpose and deployment scenarios for something like this would be? Inquiring minds are dying to know.
Thankee

[626s]

those caps give you that xtra bump in car audio bass. i have found they are not good for cb stuff. they cant recharge fast enough. hope this helps.

[Crusher]

The only way that they can even be remotely considered is if your electrical system is already a better than average system. If your system can't hold it's own now, it certainly will not make things better. Don't waste your money. Go buy another battery. Heck buying a new battery is way cheaper than trying to buy a large cap. On the same note though, when I only run a 2 pill 1446's, I have a 3 farad hooked up. Don't really see more watts, maybe 10W RMS, But I think it does help with audio. Assuming the aforementioned is applicable.

[dr_dx]

Caps are used in audio applications where you have high transient amp surges (read BASS). Standard lead acid batteries have internal resistances of 2~3 ohms where a cap has a resistance of .00xx ohms. It can deliver (up to its rated capacity) energy a lot quicker than a regular battery. In RF applications, a cap could be useful to handle SSB peaks so that you don't drop to much voltage and warble. It is basically useless for AM.

A better use of your money would be to buy an AGM (Absorbant glass mat) style of battery. There are quite a few manufacturers that make these. Optima, Exide Orbital, Deka Intimidator, Hawker Odyssey, to name a few of the more popular ones. They have the same low internal resistance that a cap does but they are infinitely more powerful. My favorite is the Orbital for the price and the 7 year warranty. They not only are capable of delivering high current quickly, they also recharge much quicker.

[Shaft]

For what a good 1 farad capacitor is going to cost you, you can buy a red top Optima battery. I rarely sold capacitor in the stereo shops I ran. I still don't like using them. 90% of the time replacing the lead acid battery with a sealed cell battery would do the job just as well as a capacitor.

In car audio, if you are using amplifiers with a fully regulated power supply capacitors really won't do anything for you. In one show car we built we were using Precision Power amplifiers. We ran 1 Optima battery dedicated to 2 amps. No capacitors.

[minirancher]

OK I do not know allot about CB, s But I know allot about car audio! Lets look at the cap thing and 1st why would you put a cap in? So your Headlights do not deem, you are putting a Cap "SMALL BATTERY" in between what draws power "RADIO" to the Power source A CAR battery in this case! WHY? If you look at Digital Capacitor It will show you DON'T USE ME! When in heavy use it will drop to 10 or 11 amps that is BAD! I do not understand why someone would put a little battery in between a large Battery and a RADIO! CAPS are a GIMMICK! MY 10 cents worth!
Keith
_________________
KDC STRYKER SR440 in the Pick up! Working on Base radio now!

[madsage]

CAPS are a GIMMICK! MY 10 cents worth!
Keith
_________________
KDC STRYKER SR440 in the Pick up! Working on Base radio now!

Capacitors oppose a change in voltage.
Inductors oppose a change in current.

Basic electronics.

[Seabee]

CAPS are a GIMMICK! MY 10 cents worth!
Keith
_________________
KDC STRYKER SR440 in the Pick up! Working on Base radio now!

Capacitors oppose a change in voltage.
Inductors oppose a change in current.

Basic electronics.

Exactly what madsage said. Just the electrical theory alone explains capacitors usefullness in a high powered system. When volts go down, amperage goes up.

[85]

Hey gang,
I was hoping someone would clue me into these big capacitors I see in audio and CB shops. What are they used for? Would anyone mind providing me a little bit of detail on what the purpose and deployment scenarios for something like this would be? Inquiring minds are dying to know.
Thankee

They are excellent for car audio systems and a complete waste of money for CB.

[Seabee]

They are excellent for car audio systems and a complete waste of money for CB.

Okay 85, explain exactly why they are a waste of money for a CB. Supporting electrical fact would be nice in your explanation. Thanks.

[mrbigshot]

the recharge time is to low to be usefull durring modulation. they do help act as a filter though. a much smaller one will work just as well as a filter though.

[85]

Hey gang,
I was hoping someone would clue me into these big capacitors I see in audio and CB shops. What are they used for? Would anyone mind providing me a little bit of detail on what the purpose and deployment scenarios for something like this would be? Inquiring minds are dying to know.
Thankee

They are excellent for car audio systems and a complete waste of money for CB.

Capacitors are good for instantaneous peaks and surges which helps car audio amplifiers. Long duration high amp keys would drain the stored charge out of a capacitor in a split second and for the rest of the key the cap is doing nothing.
It's your money.

[Flattop]

well i got to throw in my 2 cents my son wrecked his car so i took all his stereo out it was just in the shop. i currently have a 93 f150, galaxy 95t2, 8pill behind it, with three red tops in line when i key up it would still dim the lights until the alt. caught up, well my son had two 10 farad caps so i put them in line. no more dim lights no more watts but the lights don't dim it would have to help some where!