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Discussion Starter · #1 ·
I'm trying to find what size capacitor I need, good brands, and good/fairly inexpensive places to buy them.

I'm running two Alpine type r 122D's with a kenwood KAC-9105D amp

Thanks
 

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Forget a Cap.

Your money is better spent elsewhere. Save money and get a better battery or just upgrade the battery to ground wire and ground to engine block. Unless you are upgrading the alt, really no need to upgrade the alt to battery positive.
 

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Discussion Starter · #3 ·
I'd prefer getting a cap since they're cheaper than getting a new battery for my car.

I just want my lights to not dim as much or at all when the bass hits hard
 

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Great first post. My favorite place to get caps is here. Excellent selection and good prices.

Moving on to more serious matters, a search of the word "capacitor" on this forum would have preempted your OP. Therefor, I will leave you with this. Start reading:
Basic Car Audio Electronics
 

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Discussion Starter · #5 ·
I searched the site, didnt see what i was looking for...
I know what a capacitor is and does, im just looking for good quality brands...
 

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Discussion Starter · #7 ·
I get that I should upgrade the battery, alternator, and grounding...
I promise...
I just want to know what brand of capacitor is decent...
 

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Well since you are going against the grain, Pretty much anything. You just want low resistance. At least 16v rated and preferably 20v. I whatever size you want. Though seriously odds are the dimming is related to the slight voltage sag the regulator can't catch. Most likely not fixable by a cap.

I would seriously take a short piece of power/ground wire and just reground battery to car. Add the wire to the existing and just make sure the connection point is clean and bare metal. You might be surprised at the outcome. plus it is an easy test.
 

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Discussion Starter · #9 ·
Well since you are going against the grain, Pretty much anything. You just want low resistance. At least 16v rated and preferably 20v. I whatever size you want. Though seriously odds are the dimming is related to the slight voltage sag the regulator can't catch. Most likely not fixable by a cap.

I would seriously take a short piece of power/ground wire and just reground battery to car. Add the wire to the existing and just make sure the connection point is clean and bare metal. You might be surprised at the outcome. plus it is an easy test.
I appreciate you answering the question.
I was going to check everything first and look into getting a better alternator/battery later, I was just planning ahead in case I did go the capacitor route

I've looked into a lot of them and they all look pretty sketchy so I don't think I'll be doing it, so I wanted to see if I was just looking at junk or if they were all basically the same
 

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If you must go with a cap, get something rated at 20V continuous, 24V surge, <2mOhm (<.002 ohm). I've had a lanzar one that was rated at 20V continuous, 24V surge, <1.6mOhm. And before people go all ballistic, I do not have the cap to fix dimming headlights. Everything was/is fine with my system before and after the cap. I got it really cheap, so I decided to throw it in.
 

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There used to be a place on ebay that sold huge caps pretty cheap, considering, but don't know what size you want. Another option you can try that I'm going to because I have one sitting here, is get a cheap $30 jumper pack and use it or the little battery in it. A battery only helps when you drop to 12v though, so you still get some dimming, but it should help if you have bad dimming.

Yeah I got a 1f some time ago for $15 I will use when I swap amps and subs next. Mostly to help the alternator, I don't have much dimming don't need that much power for my IB subs.
 

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i know someone posted this on here before, because it's where i got it from, but i can't find that post so here it is.

After studying a little history on large 1 Farad capacitors in car audio, you'd be amazed that they even sell at all. How useful are they? What do they really do? Will a Cap 'improve' my sound quality? Will it Prevent my lights from dimming? Will it audibly affect my audio system in any way?

Before you get the truth to any of the above questions, chances are, you've probably spent $100 or more on one of these devices. However, let's study a little history regarding this issue.

A long time ago, in a land far away, 2 elves...Ok, Richard Clark & Wayne Harris (Carsound magazine and the inventor of DB Drag, respectively) separately came up with a solution to preventing their lights from dimming.

WHO WERE THESE GUYZ?

As you may know, Richard Clark is one of the founders of autosound2000 Tech Briefs, Carsound magazine, and a published author of the industry of mobile electronics. In SQ competitions, he posted a record of 1234 1st place finishes, and only ended up NOT 1st in his first event. I've heard that he had minor system problems, but judging by his record, he must have corrected it. (evidently, he needed a Capacitor )

Wayne Harris was previously a leader at Rockford Fosgate in their development. Later, in his free time, he created the organization we call DB DRAG. Wayne was the first SQ World Champion from the organization we know as IASCA (International AutoSound Challenge Association).

Both of these gurus are both legends, and considered the leading experts in the field. During their competition days, both guyz came up with a way to assist in the prevention of voltage drops. In SQ competitions, the look of your system is actually more important than the sound, and having your lights NOT dim under high playing levels is a competitive advantage.

As you may know, amplifiers are made up a bank of little capacitors, resistors, etc. What has been common engineering knowledge is that capacitors store energy, and more or bigger ones assist in balancing the power supply.

Wayne came up with the idea of putting several dozen 'little' (approx 100uF) capacitors on a circuit board to 'extend' the power supplies storage. At about the same time, or shortly afterward, Richard came up with the idea of one huge mondo capacitor (I believe it was 800,000uF or 0.8F) to do the job.

Eventually, Richard won. The large cylindrical tubes won over the complicated 48 caps strapped to a circuit board. However, what did this really accomplish? Let's start here:

WHAT IS A CAPACITOR?

Basically, capacitors are an energy storage device. Large, 1 Farad or more
capacitors store energy (electrons) between their plates. Capacitors differ
from batteries because batteries store energy in the form of chemical
energy--and rely on acid and lead plates, as the place of storage. For a more detailed
description of a capacitor, go here:

http://www.eatel.net/~amptech/elecdisc/caraudio.htm

Then on the right hand side, scroll down to CAPACITOR. Keep in mind the use
of capacitors in an audio system.

WHY DO PEOPLE BUY CAPACITORS?

The number 1 reason would have to be because their lights dim when their
system is playing HARD. In car audio, we are told that a capacitor is
designed to prevent the voltage drop associated with your lights dimming.
The number2 reason is that it is rumored to 'improve' sound quality or
'stiffen' the power supply/source.

WHY DO MY LIGHTS DIM?

Headlights brightness is in direct proportion to the source voltage. For
instance, if your car is running, system voltage is ~12.5 -14.4 VOLTS. Your
lights will be much brighter than when your car is turned off--where battery
voltage is ~12V. Most car alternators put out between 75 to 120 amps of
current. When this current draw threshold of the charging system is
exceeded, system voltage will drop as power demands are now shared by the
alternator and the storage devices (battery & cap). We are using battery
reserves beyond this point until the demand lessens

When playing your system really hard. Your lights dim because your
alternator can't keep up it's charging voltage (around 13.5V) and therefore,
demand exceeds output. When this happens, your electronic devices are
dipping into the power storage of the battery. Since the battery stores
power at ~ 12-12.5V, there is a 1.3 to 1.8V drop in voltage available. This
in turn is why your lights dim down.

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. In your case, you need 160 amps x 12 volts or or let's say 1920 watts of energy. Since a cap stores 50W, how much of a difference do you think it's going to make? A cap is basically a peashooter. W+e 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. Like SWEZ says, ・.The cap already shot its wad, an does limp til recharged・ I知 not so certain I will allow him to babysit my kids, but you get the drift. (I never said it quiet like that... and oh...I'm great with kids!)

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..


Please do not try # 6. New hairstyles are always refreshing, but if you are wearing railroad tracks across your teeth, you might have one big filling after it痴 over.

HOW CAN CAPACITORS IMPROVE SOUND QUALITY?

They can't. Sound quality is not dependant upon the presence of large bulky 1 Farad capacitors. How many 1 Farad Capacitors do you think the Boston Pops, Aerosmith, or Snoop dog use in the recording studio?

IN A NUTSHELL.......

When Richard, our fearless inventor, became World renown for winning every competition under the sun, people began copying what he did. Soon, every 'serious' competitor had a 'stiffening' capacitor--not to be confused with the 'loosening' capacitor.

WHY?

In the late 80s, people began sticking out their tongue when dunking the basketball because Michael Jordan did. Did sticking out your tongue improve your dunking ability? Same here with adding a capacitor to your electrical system.

STILL A GLUTTON FOR MORE PUNISHMENT?

Here's the Original Cap Debate.

http://www.carsound.com/ubb/Archives...-1-000307.html

Phoenix Gold's marketing guru had just posted information on how their Powercore (basically the Alumapro CAP15 in a Phoenix shell) had both stabilized their voltage and improved the sound quality. Richard called him on it (all in another post) and the marketing geek was unable to quantify any of the conditions that resulted in the voltage being HELD at 14.2V and the 'improved' sound quality.

Please do not read every stinking post as valid. There are a lot of people that have had the efficacy of capacitors inbred to their minds, and were not (and still not) convinced in the futility of a 1 Farad storage device.

In a final note, Richard relayed a quote regarding battcaps ( www.battcap.net ) as, "..The audio industry is the only place i know of where you can publish specs that show your product is useless and still be able to sell them------and whats worse is that technically ignorant people will argue against the math!!!!!!!..............RC.." when referring to the product. This also relates to most digital readout capacitors, and I wish my Archie Bunker skills could have said it better myself.
 
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No caps don't do that much. Every amp has smaller caps in it, they are not there to store power though they do, they are there to take noise out of the power and smooth the power delivery. Your battery does the same thing.

A huge cap can help, but it depends. If you are drawing your voltage down a lot a cap will not help you need an alternator to run 14v then, or more batteries to run 12v. If you only draw it down at peaks and it stays up most of the time, a large enough cap can help. A battery is way better at storing power, but only at 12v not 14. A cap is best at supplying power really fast, but a small amount of power and then it must be recharged. Think flash in a camera, they are run by a cap its the perfect use to store and release very fast.

So a cap might help with say rock music, but not with bass music because it is steady sine wave type draw not just a big drum hit, for example, where it has time and power to recharge after. So yes it can work, but not for constant draw only peaks here and there. It can help the electrical system in other ways. It will not change the sound of an amp or increase its power, it can only supply more power for an instant when voltage starts to fall. Longer than an instant if you have a huge cap. The problem today is you can buy a larger amp pretty cheap that makes the same power at 12v. That might make your lights dim even more I suppose, lol, but anyway a cap can help with a minimal problem its just not the magic people try to sell them on. Now if you have a big amp drawing a lot of power, you will need a huge cap array to supply it for a moment.
 

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If I was to use a Cap, the only ones that would go in my car would be either BRAX or HELIX.

If it's too expensive, well too bad... You asked for opinions, here's mine ;)

Kelvin
 

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SO, WHAT IS A CAPACITOR GOOD FOR?

6. A neat thing to tell your friend, "..Hey man, lick the top of this..

Please do not try # 6. New hairstyles are always refreshing, but if you are wearing railroad tracks across your teeth, you might have one big filling after it痴 over.
Hmmm.....I have this friend I don't like and.......:D
 

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Do a google image search of "Penis Pump" and turn the safe search off ;)


You have been tolt
:bowdown: :lol:

IF you're still intent on getting one...and god knows why...try Stinger.
 

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I have always installed one as a power conditioner. Kind of like a buffer to ensure that smooth power is delivered to the amps.

... After all, amplifiers have B+ Filter Capacitors for a reason.

And yes, I know it is not a silver bullet for actual power delivery/generation.
 

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If I was to use a Cap, the only ones that would go in my car would be either BRAX or HELIX.
If it's too expensive, well too bad... You asked for opinions, here's mine ;)
Kelvin
I've got 2 Brax IPC Caps which feed my Brax amps which have special circuitry for cap input with separate power supply exclusively for the caps. Music has very fast attack and sound very very accurate but no harshness.

BTW, thehatedguy, last I communicated with him still had two 2 Farads at EXCEPTIONAL price for sale.

Scott
 

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I've been able to successfully use a capacitor to filter out the AC ripple that was being pushed by my alternator. Prior to the cap, I tried everything under the sun to get the noise to go away. Then I called one of my friends in California, he told me to measure AC voltage at my battery while the vehicle was running. When I told him the AC voltage reading I picked up he said to try a capacitor AND consider replacing the alternator because the AC voltage was too high at the battery terminals (over 2 volts if memory serves correctly). Sadly, my replacement alternator did the same thing, but, the capacitor stopped my noise issue!
 
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