cap question

[Mongojerry36 10+ year member]

hey,

i have two type r's connected to a jl 1000/1 amp. My lights dim and im not too sure about how to do the big 3 cuz im not tech savvy at all. The installer from the place i got everything said i need a 25 fared capacitor. It was $300.

I dnt wanna buy something that im not sure is necessary.

Anyway, my question is: Do i need a capacitor? and if i do, what do you recommend?

thanks

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[2002XLT 5,000+ posts]

300 dollars? Good lord.

Short answer. No, you dont need it. Look up "big 3"

 

[btdickey99 5,000+ posts]

dont even spend 50 dollars on a cap...not worth it...I would suggest big 3 or additional battery

 

[Paaco1981 10+ year member]

If your installer told you to buy a 25 farad cap for $300 to fix your voltage problem stop going to him. If I was going to spend that much I would buy an HO alt.

And for $300 you could also just buy a nice Group 31 battery to go back there that would be a million times better than a cap.

 

[Mongojerry36 10+ year member]

ok thanks, i also looked up the caps nd i only need a 2 fared cap...but why is it unnecessary if it stores power and takes stress off of the battery and alernator...

and how would i connect a battery to my system??

 

[ultimate157 5,000+ posts]

it doesn't take stress away from the electrical system, it adds to it. Think of it this way: You're adding another component to your system that needs to be kept charged.

Do the Big-3 and upgrade your battery to a group 31. Check out the Deka batteries @ remybattery.com

 

[memphis_vette 10+ year member]

do not get a cap they are worthless...only thing it will help are the short blurps but ne long notes it has no chance and even if u did get one u wouldnt notice

 

[Mongojerry36 10+ year member]

so i can get away with the two type r's nd the jl 1000/1 amp without a cap?

i hear alot about the big three, i have no idea where to start as i know nothing about engines even if i have directions haha that may sound stupid but its true

i mean if i dnt bump them all the time i should be okay without making any mods, correct?

 

[Duckman 10+ year member]

This what I posted a couple days in the amp section...Like I said maybe too much info.

This is what the Zeff man says...

This was taken from Zed Audio's manual.

Stiffening capacitors - These are of NO use with our amplifiers due to the fact that the amplifiers have fully regulated power supplies. The power supplies will compensate for small volt drops which exist on the +12v power cable. The amount of current drawn by a particular amplifier would drain a fully charged 1 Farad capacitor almost instantly. Consider the theory. Energy (Joules) = Power(Watts) x Time(Seconds). The energy in a 1 Farad capacitor = 0.5CV.V= 0.5x1x12x12= 72 Joules. Let us assume a medium size amplifier such as Draconia. Let us assume that we are playing it such that all four channels (into 4 ohms each) are just clipping on the loudest musical peaks. This means that we are delivering 300 watts on peaks. The amplifier's average efficiency is about 45. The peak to average power ratio is about 20 so average power is 20 of 300 = 60 watts. The input power is therefore 133 watts. If the 1 Farad capacitor was charged to 12 volt and we remove the main source of power - the battery, the amp would remain playing for 0.54 seconds! (Put the numbers in the formula (E=PxT above and solve for time T). Now compare this to the battery. The amplifier will play for some hours (depends on actual battery of course) as compared to 0.54 seconds! So what good is a 1 Farad capacitor? Assign the above example to a Megalith playing into a 1 ohm load. Going through the mathematics the 1 Farad capacitor would keep the amplifier playing for 0.14 seconds. So if the voltage at the amplifier's power terminal dropped by say 1 volt the amplifier's power supply will correct for this on a continuous basis. The stiffening capacitor however has nowhere close to the energy reserve to compensate for a 1 volt drop. The main internal power supply capacitors hold 100 Joules of energy and these are more effective than any stiffening capacitor since they do not have to contend with the in-efficiencies of the amplifier's power supply.

Probably more than you wanted to know but at least this explains it....

 

[Mongojerry36 10+ year member]

na that helped my friend thank you

 

[mrbomb 10+ year member]

do you have any friends or know anyone that is into working on cars?

if so see if they would be willing to help you out with the big 3

 

[Mongojerry36 10+ year member]

na i dnt know anyone to be honest, i live in central jersey and there arent many places that know what it is, and many places i talk to have never heard of it

 

[casper97ta 10+ year member]

Stop going to that installer. Although he's just doing his job and trying to sell a product and make money on people not in the know. anyway, just follow these instructions for the big 3: http://www.caraudio.com/forum/showthread.php?t=152355

 

[XxSuperAdamxX 10+ year member]

If your installer told you to buy a 25 farad cap for $300 to fix your voltage problem stop going to him. If I was going to spend that much I would buy an HO alt.
And for $300 you could also just buy a nice Group 31 battery to go back there that would be a million times better than a cap.

Agreed.

 

[Lakota 5,000+ posts]

We really need a stickied thread for caps, and If someone posts another thread about a cap the thread should be closed.