Capacitor for better SQ?

[AndrewHD 10+ year member]

Hey guys, I've been reading a lot online about how capacitors give better sound quality due to stiffening of voltage to the amps. What are your thoughts or experiences on this? I already have a high output alternator but there is still a voltage drop of 14.4 to 13.8 volts on music

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[trumpet 5,000+ posts]

A standard "stiffening" capacitor will have a voltage drop, so that isn't going to raise your voltage above 13.8. What power wire do you have and how many runs?

 

[AndrewHD 10+ year member]

Good point. I have one run of 0 gauge for the sub amp and a separate 4 gauge run for speaker amp. Problem is I don't really want to add more weight with another battery and I don't see the drop to 13.8v as being very harmful to the amps

 

[winkychevelle 10+ year member]

Bank of 6 supercaps wired in series will help

 

[cfox10 10+ year member]

full run for ground?

try doing two runs of power to each amp

 

[jrdnhsnbrg 10+ year member]

Yeah caps do very little to nothing, and an XS Power D680 weighs less than 20lbs and doesn't cost more than a somewhat decent capacitor.

 

[keep_hope_alive Premium Member]

super caps are superior to extra batteries for car audio and will help maintain the alt output while extra batteries will only help maintain their float voltage. but a super cap bank is 500F or higher. the standard 1-5F caps you see are useless.

but supercaps are also much more expensive - $65 each and you need banks of 6 in series (they are 2.5V-2.7V each).

 

[bubbagumper6 5,000+ posts]

A standard "stiffening" capacitor will have a voltage drop, so that isn't going to raise your voltage above 13.8. What power wire do you have and how many runs?

Why would a capacitor produce a voltage drop?

 

[jrdnhsnbrg 10+ year member]

Because the cap immediately (and somewhat violently) recharges after it discharges which therefore causes a drop, unlike a battery which slowly evens out. This is also why you need a resistor or 12V light to charge the capacitor initially, otherwise you could fry the wiring or do serious damage to the capacitor.

 

[trumpet 5,000+ posts]

Why would a capacitor produce a voltage drop?

Look up ESR.

 

[AndrewHD 10+ year member]

Ok, I was thinking about doing the Rockford 10 farad mainly for looks and to help the interior lights from dimming. I'm thinking a cap might be easier than another battery since the battery should be the same type and age as the one in front

 

[jrouter76 10+ year member]

Ok, I was thinking about doing the Rockford 10 farad mainly for looks and to help the interior lights from dimming. I'm thinking a cap might be easier than another battery since the battery should be the same type and age as the one in front

Big 3 for dimming,and a 2nd battery(gel-cell) with 2 runs of 1/0 wiring would do much better then the Eye Candy(cap).lol

 

[phemps 10+ year member]

Big 3 for dimming,and a 2nd battery(gel-cell) with 2 runs of 1/0 wiring would do much better then the Eye Candy(cap).lol

The big three will not always solve light dimming without reserve power. Actually often times it may make it worse because it allows your amps to draw more current and taxes the rest of your electrical system harder. but yes with those three things your much better off. Battery doesn't necessarily have to be a gel but at least go with AGM

 

[Chrispy 10+ year member]

Bank of 6 supercaps wired in series will help

super caps are superior to extra batteries for car audio and will help maintain the alt output while extra batteries will only help maintain their float voltage. but a super cap bank is 500F or higher. the standard 1-5F caps you see are useless.
but supercaps are also much more expensive - $65 each and you need banks of 6 in series (they are 2.5V-2.7V each).

^Yes

Either go super caps or forget about it. But do your research first.

 

[Jepalan]

Look up ESR.

I don't see how ESR applies to this discussion of voltage drop at all. Capacitors are not installed in series with the power feed. They are installed in parallel across the power terminals. In general, across the operating freq range of the cap, ESR will increase at lower frequencies and decrease at higher frequencies up to the self-resonant frequency of the cap. Once charged the capacitor creates no DC load on the system, and very little additional dynamic load (compared to the amp and sub).

I don't follow the argument that a cap causes voltage drop. That said, I don't use caps in my sub installs, so I'm not an expert. Would love to hear a better explanation and see some measurements of actual voltage drop caused by cap installs.