Question on capacitors

[b0ssfr0mdabay]

I have a 2 channel amp, should i hook up one smaller capacitor to each channel or just one big one? thanks in advance

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[malic 10+ year member]

none at all

 

[vincent714028 10+ year member]

If you wanted to use a capacitor one big one will be fine, but I've used them before and I can't tell a difference.

 

[Megalomaniac 5,000+ posts]

i dont understand the question?

 

[SW9152 10+ year member]

idk why youd need 2 for one amp. i had one and it helped the lights dimming a little bit but i was running way mroe watts than my charging system could handle in the first place. i wouldnt expect much outta puttin one in. IMO not worth more than $30 which is about what i paid for my 1.5 farad cap.

 

[SW9152 10+ year member]

you do under stand you put it inline with the power wire not the speaker output right?

 

[Megalomaniac 5,000+ posts]

i hate to burst your bubble op. but the cap is doing more harm then helping. A cap is being used as a bandaid. its covering up your electrical voltage problem. While your eyes are seeing dimming with the cap out, you can clearly see you are having a problem, but with the cap its covering up fooling you to believe you have solved the problem. In the long run, your batteries will die out sooner, and your alternator is taking a beating from trying to keep up the charge for the demand of power. my suggestion to you is to start by getting a deepcycle battery, then upgrade your wires(with a thicker guage) coming from your alty to bat(as well as grounds). then if problem still occurs, upgrade to a higher amp alternator.

so long story short solve the problem, dont cover it //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

edit: cap goes on the power wore coming from battery to amp, not the speaker outputs, so only 1 cap would be used.

 

[bigbang 10+ year member]

Would you rather tie a steel rope around your neck or a rubber one? I still believe a cap is a good idea because if you look at a graph of voltage from your battery measured acoss fractions of a second, the graph with an inline capacitor will be smoother with smaller peaks and valleys. Linear everything is the way to go. Even with a 250amp alternator, 0 gauge, and multiple low resistance deep cycle batteries, the cap still has the lowest ESR equivalent series resistance and smooths out voltage demands and gives the amp power a fraction of a second before the upgraded electric system will. A battery relies on a chemical reaction which takes longer than a capacitor releasing power stored in foil and electrolyte, and even with the beefed up alternator, the power has to travel through 15 feet of wire to get to the trunk. Even without an upgraded electric system, I think it is better for the longevity of all the cars electric systems and CPU's if the voltage doesnt jerk around so much. It will still dip low, but its like getting hit with a rubber mallet in the head repeatedly vs a sledgehammer. In the end the stock battery and alternator will die, but not as fast.

 

[Megalomaniac 5,000+ posts]

Would you rather tie a steel rope around your neck or a rubber one? I still believe a cap is a good idea because if you look at a graph of voltage from your battery measured acoss fractions of a second, the graph with an inline capacitor will be smoother with smaller peaks and valleys. Linear everything is the way to go. Even with a 250amp alternator, 0 gauge, and multiple low resistance deep cycle batteries, the cap still has the lowest ESR equivalent series resistance and smooths out voltage demands and gives the amp power a fraction of a second before the upgraded electric system will. A battery relies on a chemical reaction which takes longer than a capacitor releasing power stored in foil and electrolyte, and even with the beefed up alternator, the power has to travel through 15 feet of wire to get to the trunk. Even without an upgraded electric system, I think it is better for the longevity of all the cars electric systems and CPU's if the voltage doesnt jerk around so much. It will still dip low, but its like getting hit with a rubber mallet in the head repeatedly vs a sledgehammer. In the end the stock battery and alternator will die, but not as fast.

If you have a good amplifier then you should never need a cap for the voltage curves, because if the amp was built properly it should have its own good electrical components inside that amp...

 

[bigbang 10+ year member]

Every amp I have ever owned has had some sort of capacitor bank inside them, but they didn't help with my headlights flashing and voltage jumping all over the place. I have owned Rockford Fosgate and MTX amps. How much capacitance should a well designed amp have built in? You ever seen the Rockford Fosgate T15kW amp in Car Audio's June 06' magazine? Well they claim that with a proper electric system that the amp can produce 15,000 Watts RMS. Not a typo. And they use some ungodly capacitor inside designed specialy by the power industy, which is supposed to be 5500 times more efficient than a normal electrolyte capacitor for a given size. Anyway, since most all amps have built in capacitance, more cant hurt right? Helps regulate the voltage to a better degree. Otherwise why have capacitors in amps at all if they are totally useless?

 

[Megalomaniac 5,000+ posts]

the t15k uses the hybrid technology capacitor that are in cars. and they are 400 farads each(using 180 of these)! so it would take quite a few to actually help out.

If you ever really notice amplifiers running at 1 ohm than 2 ohm suffer more with the dimming. I went from an eD NINe.1 to a Zapco 1100.1 and that 2 ohm electrical made a hell of of a difference. However i now have a d2 mx so i am running at a 4ohm load(800 watts), which is even better for my electrical. I do have a 200a alty to back up the power. Just goes to show an amp does make a difference.

 

[DejaWiz 5,000+ posts]

the t15k uses the hybrid technology capacitor that are in cars. and they are 400 farads each(using 180 of these)! so it would take quite a few to actually help out.
If you ever really notice amplifiers running at 1 ohm than 2 ohm suffer more with the dimming. I went from an eD NINe.1 to a Zapco 1100.1 and that 2 ohm electrical made a hell of of a difference. However i now have a d2 mx so i am running at a 4ohm load(800 watts), which is even better for my electrical. I do have a 200a alty to back up the power. Just goes to show an amp does make a difference.

Good info and here's an explanation of amplifier loads and current draw to back up Mega: http://www.bcae1.com/hcvsnohc.htm

For the lazy:

High Current Amplifier:

No load rail voltage: +/- 36 volts

RMS voltage delivered into a 1 ohm load per channel: 19.6 volts

RMS power into each 1 ohm stereo load: 384 watts

Current draw at full power: 101 amps

Standard 2 Ohm Stable Amplifier:

No load rail voltage: +/- 47 volts

RMS voltage delivered into a 2 ohm load per channel: 27.7 volts

RMS power into each 2 ohm stereo load: 384 watts

Current draw at full power: 76 amps

 

[bigbang 10+ year member]

Nice selection of amps. I just have a couple MTX 1501D's and a 1004. Solid performers but not as exotic. I don't think running an amp at low ohm loads is worse, you just have to keep check on your total current consumption. After all 1100 at 2 ohms is almost the same as 1100 at 1 ohm as far as your electric system cares. I think the amps efficiency just goes down as you halve the impedance and you generally get a little less than a doubling of wattage. Dont you think a giant cap would at least help for a split second on a bass burp regardless of a great electric system/amps ?

By the way, off the cap subject, how much was the labor for your alt. upgrade, did you have to replace all the factory alternator wiring, does the alt mess with your vehicle electric or fry any of your relay boards or any of the horror stories I have heard about? How much is involved? Thanks.

 

[bigbang 10+ year member]

Good info and here's an explanation of amplifier loads and current draw to back up Mega: http://www.bcae1.com/hcvsnohc.htm


For the lazy:

OK, I guess alplifier effeciency drops alot and current consumption increases alot at lower loads. Good to know, I'll keep this in mind in the future.

 

[Megalomaniac 5,000+ posts]

Nice selection of amps. I just have a couple MTX 1501D's and a 1004. Solid performers but not as exotic. I don't think running an amp at low ohm loads is worse, you just have to keep check on your total current consumption. After all 1100 at 2 ohms is almost the same as 1100 at 1 ohm as far as your electric system cares. I think the amps efficiency just goes down as you halve the impedance and you generally get a little less than a doubling of wattage. Dont you think a giant cap would at least help for a split second on a bass burp regardless of a great electric system/amps ?
By the way, off the cap subject, how much was the labor for your alt. upgrade, did you have to replace all the factory alternator wiring, does the alt mess with your vehicle electric or fry any of your relay boards or any of the horror stories I have heard about? How much is involved? Thanks.

As long as you do the Big 3 you're fine. you wont see anything frying. labor wasnt much, since my alty is right in front . may be harder on some vehicles where the alty is down under.

I would rather run a 2 ohm stereo any day of the week over a 1 ohm load.

There is a reason why Zap, Audison, & steg are expensive aside from the better SQ. A higher wattage at a lower impedance is task on its own. Regulated power.

I rather throw in an extra battery than a capacitor. at least you will have more power on reserve. there is a sticky over at ROE thats explains a bit in detail on capacitors.

OK, I guess alplifier effeciency drops alot and current consumption increases alot at lower loads. Good to know, I'll keep this in mind in the future.

//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif