What would be better for capacitor

fieryhooligan
10+ year member

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Okay guys, I might catch it for this, but i am putting a capacitance system in my car to remove electrical noise.

for info see here is a video about electrical noise in audio systems

This is really only for people who use caps and/or know a lot about them

Should i use (for instance) 1 5-farad cap, or 5 1-farad caps, and what is a hybrid cap?

 
SQ guys love them, pretty common in their cars, they use them to smooth voltage ripple, if you have alt whine this wont fix it, you need to fix the alt whine and not put a bandaid on it. I think maybe you are misunderstanding

On another note to me most of those SQ cars sound like, a system that is flat on the RTA sounds like poop

 
SOOOOOOOOOOOOOO, just so that i understand completely, while a capacitor may decrease electrical noise from the alt, engine, etc, it may flatten out my response curve, and if i upgrade the big 3 and do a dual batt system with two batts, i will see NO increase in quality or power or anything, even if i have money to waste?

 
A couple of things here.

Yes, there is AC ripple on the power system in your car. Amplifiers and head units have capacitors internally that filter that out. Your system won't be cleaner sounding with an external capacitor.

The Big 3 and extra batteries are done to provide stable voltage during the high power draw of big amps. They're not intended to improve sound quality by removing alternator noise. You may get more peak power if you are losing voltage in the wiring.

I'm not sure what you mean by "it may flatten out my response curve"

 
the battery filters ac ripple from your alt, not a capacitor. and the response curve depends on many factors but a capacitor (not counting crossovers) is not one of them.

(large > 1farad) capacitors are only used to stabliize voltage. which should be fixed with a good alt and batts anyway.

 
IMO if you "need" a capacitor you should have bought a well built amplifier with enough capacitence on the power supply in the first place. If you have noise, a cap is not your answer, a proper instal is.

 
Yes, there is AC ripple on the power system in your car. Amplifiers and head units have capacitors internally that filter that out. Your system won't be cleaner sounding with an external capacitor.
Thanks for that... good to know.

I'm not sure what you mean by "it may flatten out my response curve"
I was refering to this

On another note to me most of those SQ cars sound like, a system that is flat on the RTA sounds like poop


SQ guys love them, pretty common in their cars, they use them to smooth voltage ripple, if you have alt whine this wont fix it, you need to fix the alt whine and not put a bandaid on it.
I don't have alt whine, im just trying to forsee all possible outcomes of my new build.

(large > 1farad) capacitors are only used to stabliize voltage. which should be fixed with a good alt and batts anyway.
So if i replace the original batt and add a second, i would see no additional voltage stabilization by adding a cap?

IMO if you "need" a capacitor you should have bought a well built amplifier with enough capacitence on the power supply in the first place. If you have noise, a cap is not your answer, a proper instal is.
I don't have noise yet, im just trying to forsee all possible outcomes of my new build.

So what i'm getting is if i do the big 3 and batt replacement/addition, i will take care of my voltage stability, and if my alt is whining, the only thing to do is replace it.

So basically caps are useless under those conditions? what about helping to eliminate ac ripple in between the alt and the batt?

Does that all sound about right?

 
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If you search the forum you'll find that the consensus around here is that they are worthless, and have been proven to do next to nothing. The correct way to deal with your power is to have an adequate alternator, upgraded wiring ("big 3") and in some cases an additional battery - though I'm personally not sure when that's actually needed. Start with the basics.

The comment made above:

I was refering to this
Originally Posted by jdawg

On another note to me most of those SQ cars sound like, a system that is flat on the RTA sounds like poop
He's saying that systems set up with an RTA (as mentioned in your reference video) tend to sound lifeless because the equalization is too "flat". A purist can argue that perfectly flat frequency response is the only way to go, but it's really just a starting point for final tuning.

 
A couple of things here.

Yes, there is AC ripple on the power system in your car. Amplifiers and head units have capacitors internally that filter that out. Your system won't be cleaner sounding with an external capacitor. wrong...

The Big 3 and extra batteries are done to provide stable voltage during the high power draw of big amps. They're not intended to improve sound quality by removing alternator noise. You may get more peak power if you are losing voltage in the wiring. A proper ground is how you get rid of engine noise.

I'm not sure what you mean by "it may flatten out my response curve"

It will not flatten out your response curve at all

 
Here is where a lot of the confusion lies.

Back in the late 80's through the early 2000's, a lot of shops and individuals alike used caps as a "band-aid" fix for voltage drops.

Most of these installs consisted of amps in the 250 - 1000 watts RMS range. Not the huge mega watt amps of today (1500++) Most of the charging systems were using generators/alternators of 45-95 amps.

When you have a lack of charging current, insufficient wiring, lack of storage capacity (battery), or a combination of any of these - you have a voltage drop.

A cheap and easy fix for a weak system was a 1 -2 Farad cap. Phoenix Gold, Stinger, BattCap, and several other manufactures made huge capacity "capacitors" that were more like a hybrid between a capacitor and an AGM battery. These were usually 5-25 Farad or higher.

When Absorbed Glass Mat batteries became cheaper around the early 2000's, there was not much use for capacitors anymore. Even a small AGM battery has several times the capacity of even the largest capacitor. When you factor in the price of a small AGM battery verses a large capacitor like a BattCap or PowerCore (Phoenix Gold), it doesn't make any sense to buy a capacitor anymore.

If you want to maintain voltage in excess of 13-14.4V, you will need a high output alternator. If you want to maintain adequate current for your amps and have voltage above 13V, you need a good AGM battery and proper wiring, along with 20-50% more charging capacity than your maximum current draw. A lot of people don't realize that you will not be drawing a constant 270+ amps so there is not really any need for a HO alternator unless you play test tones for long periods of time. If you design your system for the current you intend on actually drawing, you can save quite a bit of money. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 
Here is where a lot of the confusion lies.
Back in the late 80's through the early 2000's, a lot of shops and individuals alike used caps as a "band-aid" fix for voltage drops.

Most of these installs consisted of amps in the 250 - 1000 watts RMS range. Not the huge mega watt amps of today (1500++) Most of the charging systems were using generators/alternators of 45-95 amps.

When you have a lack of charging current, insufficient wiring, lack of storage capacity (battery), or a combination of any of these - you have a voltage drop.

A cheap and easy fix for a weak system was a 1 -2 Farad cap. Phoenix Gold, Stinger, BattCap, and several other manufactures made huge capacity "capacitors" that were more like a hybrid between a capacitor and an AGM battery. These were usually 5-25 Farad or higher.

When Absorbed Glass Mat batteries became cheaper around the early 2000's, there was not much use for capacitors anymore. Even a small AGM battery has several times the capacity of even the largest capacitor. When you factor in the price of a small AGM battery verses a large capacitor like a BattCap or PowerCore (Phoenix Gold), it doesn't make any sense to buy a capacitor anymore.

If you want to maintain voltage in excess of 13-14.4V, you will need a high output alternator. If you want to maintain adequate current for your amps and have voltage above 13V, you need a good AGM battery and proper wiring, along with 20-50% more charging capacity than your maximum current draw. A lot of people don't realize that you will not be drawing a constant 270+ amps so there is not really any need for a HO alternator unless you play test tones for long periods of time. If you design your system for the current you intend on actually drawing, you can save quite a bit of money. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif
You may want to fix that last part. A stock 100 amp alternator is not gonna support you 6000 or 7000 watt system, no matter how many batteries you have. A battery is a band aid and that's it. Batteries will do you no good if your alternator cannot keep up with charging them.

 
It depends on if you are playing that 6000 - 7000 watt system for a 30 second burp, or if you are playing it for 30 minutes. If you are playing for 30 minutes, Yes you will need a HO alt. If you are playing for 30 seconds, No, you can get by with a bank of batteries. People who design and build hydraulic systems for lowriders use a bank of batteries for the high current spikes of the pumps firing up, but generally don't have a HO alt because they are only drawing current for a few seconds at a time using 500+ amps. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 
It depends on if you are playing that 6000 - 7000 watt system for a 30 second burp, or if you are playing it for 30 minutes. If you are playing for 30 minutes, Yes you will need a HO alt. If you are playing for 30 seconds, No, you can get by with a bank of batteries. People who design and build hydraulic systems for lowriders use a bank of batteries for the high current spikes of the pumps firing up, but generally don't have a HO alt because they are only drawing current for a few seconds at a time using 500+ amps. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif
^ ding ding ding

we have a winnar

 
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