Phoenix Gold Phorum

Are PG Capacitors any good?

All electrolytic caps are very similar.....find one with the specs you want and look for and buy the cheapest one that has the same specs.


There are just a handful of manufactures that make the cap’s the big difference between brands is the shrink wrapped label on them.

Wink wrote:Are PG Capacitors any good?

If your just running that one amp (Octane), IMO you really don't need one. Some one help me out, am I correct?

notihng like a good ole cap..

quoted from another source.

HOW MUCH POWER DOES A CAPACITOR STORE?

1 Farad = 100 joules or 100W/second
850cca battery = ~2,200,000 farads

For storage purposes, you'd need ~2,200 1 Farad capacitors to equal the energy of your battery.

Due to its impedence (ESR & ESL), a cap's energy is only 50% available. What's worse, is that in order for a 1 Farad cap to discharge, first the alternator output must have maxed out, and the voltage must have dropped around 1.5 volts. But I thought a cap was supposed to prevent that (voltage drop)!!!!!????? Yep, you got the point.


IF A BATTERY = 2,200 CAPS, THEN WHY BUY A (PUNY) CAP?

My question exactly. Marketing is the reason why people buy caps. In many cases, upgrading wiring will help your system get the maximum transfer of current. Once that has been reached, adding a capacitor may have a minor effect on your system. 50W over the course of a second is not a lot of power considering an amplifier may draw 2000W to put out 1400 watts. Let's look at the situation from a resources standpoint.

Alternator 80 amps
Car accessories (minus stereo) 40 amps
A large Car Audio system (DRAWS ) ~200 amps AT FULL OUTPUT

In this case, you have 240 amps of draw, but only 80 amps of current from the alternator. Since a cap stores 50W, how much of a difference do you think it's going to make? A cap is basically a peashooter. We need a Howitzer cannon here, to do the job well.

Also, Once a cap is discharged, where does it get it's power from? The alternator, which is already overloaded. Once a cap is discharged, it's worthless.

SO, WHAT IS A CAPACITOR GOOD FOR?

1. Audio Jewelry- impress chicks with large cylindrical shiny thingy
2. Extra weight in winter time
3. A very POOR... BUT expensive distribution block
4. A projectile in the event of a crash
5. Rolling pin--for cooking purposes
6. A neat thing to tell your friend, "..Hey man, lick the top of this..

Caps are pretty worthless as far as external power sources go, unless you've already got enough juice to power the amps. In that case, they help smooth the power going into the amps.

Its the one thing I have never used in any of my cars, get your self a decent battery, I typically use the Optima Yellow top.

That's pretty much what I was thinking myself. Caps are a help but cover all the other bases first, in order:

1. wire
2. battery
3. alternator

Right-o, they are more of a bandaid that just helps a larger issue.

gridracer wrote:
What's worse, is that in order for a 1 Farad cap to discharge, first the alternator output must have maxed out, and the voltage must have dropped around 1.5 volts.

that's not correct. in fact i only recommend a cap when an otherwise capable charging system (i.e. alternator) is already in place. when listening to dynamic listening materials a cap can in fact be very useful. during the dynamic peaks the cap will discharge VERY quickly but won't recharge until there is another "lull" in the music.

dedlyjedly wrote:

gridracer wrote:
What's worse, is that in order for a 1 Farad cap to discharge, first the alternator output must have maxed out, and the voltage must have dropped around 1.5 volts.

that's not correct. in fact i only recommend a cap when an otherwise capable charging system (i.e. alternator) is already in place. when listening to dynamic listening materials a cap can in fact be very useful. during the dynamic peaks the cap will discharge VERY quickly but won't recharge until there is another "lull" in the music.

jed wins...hes right.

dedlyjedly wrote:

gridracer wrote:
What's worse, is that in order for a 1 Farad cap to discharge, first the alternator output must have maxed out, and the voltage must have dropped around 1.5 volts.

that's not correct. in fact i only recommend a cap when an otherwise capable charging system (i.e. alternator) is already in place. when listening to dynamic listening materials a cap can in fact be very useful. during the dynamic peaks the cap will discharge VERY quickly but won't recharge until there is another "lull" in the music.

Go argue with Richard Clark then that is a quote from his article.

i would but its worthless, if you notice all the threads based off of
the cap senerio never takes in concideration a stout power supply
to begin with.

i run caps, do they work, yes i been through this in the old pg forum
actually i believe me and jbondox were trying to educate people about it
but to make it a shorty story, when i had a stock alternator with a decent
battery it didnt make a world of difference. ran a set of four guage jumpers from my nissan witha 225 amp alternator and did a test with and with out the cap. the voltage was smoother and more stable with the caps
i used 1 farad caps on each amp.

so again its not a quick fix or a cure for a piss poor power supply but on a proper set up it will help overall voltage stabalization on demanding peaks
because your regulator in the alt. is not that fast, niether is a battery
unless you have a kinetic which even they told me a cap is just alittle faster at discharging but they couldnt tell the difference between there testing.

so if set up right a cap is benefical but i have seen instances where it doesnt do a damn thing.

so it depends on what your trying to do. put a bandaid on cancer
well then it aint gonna work.


btw i just got a kinetic 2000
jesus now that is a battery.

Well my alternator is only a 90 amp and i belive my battery has 800 CCA or sommin like that but i was told that i wouldnt be able to push my amp because my amp has a 60 A draw...and im not spending $250 Cad on a friggin alternator thats not Chrome..lofl

I still think you don't need one.

i think as long as you listen to music and you have very solid
tranfer of current to your amp then you will be fine.
you may expereince some dimming on harder notes but then thats
physics at work.
check your voltage at battery with your volume where you would
really hammer onit.
if you have severe voltage drops then we will continue
but if its stable at no lower then 12.6 to 13 then your all right.
now check it at the amps and see if its the same or worse
if its worse then up front you have a bad connection or high resitance
in your path
then again we will continue.

Wink wrote:Well my alternator is only a 90 amp and i belive my battery has 800 CCA or sommin like that but i was told that i wouldnt be able to push my amp because my amp has a 60 A draw...and im not spending $250 Cad on a friggin alternator thats not Chrome..lofl

I would take an alt upgrade for 250 any day, no chrome necessary. The cheapest ones I have found around here are $600 and they look like stock. I have a VW and a Mitsubishi and neither of them offer alt upgrades for cheap...

i would stay away from chrome anyway
it holds heat which isnt so great for your regulator unless its external

alsodont knock the investment in a alternator.
it makes alot of difference when running a crap load of pwer.
trust me.

i would take the $250 and invest in alot of big ass wire, like 2/0 and lot s of it. Then you shouldn't need a cap.