in my 94 ford f 150 ex cab i have 2 10'' sony explods with a 1200 watt absolute amp and a pioneer cd player.... i was talking to a friend and he said that i sould put in a capacitor so i dont drain my battery..is this true

thanks Hondamx320

 

A cap isn't going to keep a battery from draining. If memory serves, it is there to help provide full power when the bass really hits, since it will pull it from the cap and not directly off the battery.

With your setup, a cap is probably a waste. I don't have a cap on my setup, and I run 2 amps. I increased the battery to a redtop Ultima, to help. With a standard battery my headlights would dim when the bass was hitting.

Later

 

save yourself the money,DONT buy a capacitor.

 

Agreed, use money for higher capcity battery.

 

A cap is going to be a waste of money in this case. I would go with red-top Optima battery, and they don't cost much more than a capacitator either.

 

Um fellas, a capacitor on amps that have power outputs over 1000w is a good idea. Especially is the amp will be outputting this kind of power consistently. It may seem like a waste of money, but I assure you it is not. Not so much for battery life, but for alternator life. Batteries are only drained because the alternators can't supply the power fast enough to charge them.

 

A capacitator is not going to help with anything except on a brief peak bass hit, say when listening to music and the drummer uses his bass drum, and then the cap only acts as a closer power source and gives when the initial "hit" occurs.

If battereies are drained because alternators can't supply the power fast enough, then how come the cap is wired in at all? The alternator is going to run if the cap is on there or not, the cap doesn't get it's power from the battery, it gets it from the alternator and if the alternator isn't running it gets the power from the battery. So how does this do any good for the alternator except get power from the battery where it has to be charged again, therefore the alternator has to engage? The best thing to do, if you're having any problems is the Big 3 upgrade, google it and you'll know what I'm talking about. If that doesnt suffice upgrade the alternator. If you're a true audiophile that spends more money on your sound system than your car is worth, buy a capacitator.

And also, that amp wouldn't put out that power consistently.. if it did, he probably wouldn't have back windows.

 

ok this is for those who prefer to be technical rather than typing in layman's terms.....

A stiffening capacitor charges like a battery. But, unlike a battery, the stiffening capacitor is designed to quickly release power on demand. This quick burst of power helps the amplifier to produce deep bass notes when it needs it. In between deep bass notes your battery and alternator re-charge the cap allowing it to be ready for the next deep bass note. This battery voltage assistance reduces voltage induced amplifier clipping, increases transient response, increases bass punch, and increases amplifier and alternator life. Stiffening capacitors should be mounted as close to the amplifier as possible. One of the other benefits of stiffening capacitors is the ability to reduce line loss. The power cable itself creates line loss. Long runs of power cable associated with mounting amplifiers in car trunks create line loss, especially during deep bass notes. Stiffening capacitors help maintain appropriate system voltages at the amplifier.

If you decide to go with a stiffening capacitor, then be sure to place an appropriate fuse between the capacitor and the amp/battery.

 

302V8 is dead on. A stiffening cap is highly recommended for systems that have any significant power drain. By stiffening the power source (battery/alternator), they enable the power source to provide sustained power for rapid, transient burst needed for higher power systems. This power enables the amplifier to operate un-distorted (with everything else being equal) when extra power is needed to sustain lower-frequency output - even when the amp is operating below its maximum output. Without a cap, the amp can easily distort these lower frequency outputs that (typically) go to subwoofers, damaging the woofer(s) or amp. Of course, RomerB2 is correct also in that, if you're continuously taxing your system's available power, you should seriously consider improving the power source (higher output alternator, an extra alternator, separate battery suited for this type of application, etc.)

There are some good sources out there for cheap capacitors. Circuit City or Best Buy will hit you with over $100 typically, but you can by 1 farad or above caps from various Web sites for $30 or $40. A cap is a cap, so it doesn't need a name brand, fancy digital display, etc.

 

302V8 is dead on. I have a question, when you bass hits, do your headlights dim?

 

Tad, if your headlights dim when the bass hits, then everything else will dim too, i.e. instrument panel and dome light. A stiffening capacitor will help prevent this. If your headlights still dim after installing a capacitor, then consider going with a bigger capacitor or installing more than one. Be sure the capacitor are installed in parallel not series. A general rule of thumb for choosing capacitor size is :

100,000 Microfarad (.1 Farad) per 100 watts of amplifier power, or 1 Farad per 1000 Watts.

Up To 500 Watts .50 Farad
500-1000 Watts 1.0 Farad
1000-1500 Watts 1.5 Farad
2000 Watts 2 Farad

Af far as the voltage rating on the capacitor, you can figure that typical automotive charging systems vary between 12vdc and 14.5vdc with average alternator output being somewhere in the vicinity of 13.8vdc. Most stiffening capactiors for car audio systems are rated at 20vdc and 24vdc surge. I wouldn't recommend buying one that is rated less than 16vdc. Bigger is better in this case.

 

302V8, I thought that comment would spur some responses. Yes everything will dim, however often times the first thing people notice is the headlights up against a wall or garage when you are pumping some bass.

 

Ok maybe you are looking at the headlights dimming as a good thing. I mean it looks like the headlights are dancing to the bass. Not controlling that power surge is hard on the alternator.

 

I couldn't agree with you more. I like to troubleshoot to find the problem, then fix it. I don't like the shotgun method. Oh lets add another (fill in the blank)

 

That system is not putting out more than 500Watts, and this is at FULL volume. Those Xplods are 250RMS, if even that. Your battery will drain only when engine is not runnning, capacitor or not. When engine is running, don't worry about it. If lights are dimming, try upgrading your Wiring. Not just the amplfier wiring, but the battery and alternator wiring as well.