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i can't decide whether to go with a nice capacitor like a 5 farad or a 2nd battery what would be best for the money nd performance:)
 

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NVSHSKR said:
What do you want a 2nd battery for? It's like comparing apples and oranges, each one serves a different purpose.
Well, I'm thinking one for starting purposes only, and the other for ICE. I realize there would have to be some sort of alternator upgrade/change, just curious that's all.
 

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Your best bet would be a rewound/high output alternator, an OPTIMA Battery, and a nice cap for your amps.

I know, I fried my alternator and battery at the same time.
 

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your best bet is to get a highoutput alternator and a yellow top cause caps drain your battery and are a waste of money
 

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Another Battery

This is a broad question. What are you running? On my truck I had a high amp alternator and three yellow top optima batteries. It all depends on what you are running why you feel that you need this. Personally I feel that capacitors are a huge waste of money. I would rather run a bigger alternator and two yellow top batteries.
 

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we have 2 batteries ones going in the back to power the tunes. add a Tsunami battery block and a 180 amp alt they have, it aint cheap but it works awsome.
 

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5 FARADS?????? how much power are you plannign on running????? Thats over kill i think!!! DImming can also be caused by the type of power supply in the amp. A capactior does not kill your battery UNLESS its defective meaning shorted out then there will be a constant draw of current on the battery due to the shorted out cap. The cap is there to maintain the voltage and supply high current during high current pulls, the capacitor reacts faster than a bettery ever will. And will keep the voltage from dropping to low.How capacitors work.

No in order to run a second battery an isolator is suggested, like those found in motor homes, the altenator connects to the main input and each battery has its own output.
 

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Skeeter said:
A capactior does not kill your battery UNLESS its defective meaning shorted out then there will be a constant draw of current on the battery due to the shorted out cap. The cap is there to maintain the voltage and supply high current during high current pulls, the capacitor reacts faster than a bettery ever will. And will keep the voltage from dropping to low.How capacitors work.

No in order to run a second battery an isolator is suggested, like those found in motor homes, the altenator connects to the main input and each battery has its own output
Caps suck when you want to run a system. Sealed battery is the way to go I know this from experience. I got mine from kinetik www.kinetikaudio.com. It gives you a lot more options in terms of what you can run. Why run 6 caps when you can get 1 battery?
 

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Damn that calucator on that site shows the HC1400 for my little system and its $350!!!! My 1 farad cap and battery are doing just fine. I should have got in the sound off just to see what my single 12 hits.

Guns4sale didnt you win that soundoff with your Mustang at Tejas Toyota? Does taht have this power cell in it?
 

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Skeeter said:
Damn that calucator on that site shows the HC1400 for my little system and its $350!!!! My 1 farad cap and battery are doing just fine. I should have got in the sound off just to see what my single 12 hits.

Guns4sale didnt you win that soundoff with your Mustang at Tejas Toyota? Does taht have this power cell in it?
I had the xB that won ;) and I have a power cell in it under the front seat. 2400w monster one. Its expensive but with running 3 amps and that big ass 15 i need all the power i can get.
 

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5 farad is NOT overkill. To match the amp output you should have 1 farad for every 200 amps. However, do NOT buy a Power Accoustik cap because they are crap, and do not help anything. I'm starting to question to usefulness of caps myself. That's why I'm running a 200A alt. on mine whenever I get the money...
 

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There's so much misunderstanding about caps for use in car audio.....whether they are needed, "do I need a cap?", "caps don't work", "get a battery instead", "do the big 3", "buy an alternator", "I have a cap and my lights still dim"...etc

First, don't get a cap to fix dimming lights.....although they sometimes can fix this. Caps aren't a battery, they aren't an alternator and they don't create any voltage, nor are they a replacement for "the big 3" .........they work in conjunction with any and all of these and act as an energy storage buffer to instantly(faster than any battery ever could) supply this energy to your amps during large transients. If your system constantly exceeds this energy buffer then you need to beef up the weak link in the chain elsewhere in your electrical system.

Not all caps are created equal.......stay with the 1 farad canister types and your usually pretty safe, the rule of thumb is 1 farad for every 1k watts. What makes a cap desirable for car audio is it's ultra-low ESR(resistance). An ESR of .001 is ideal, .002 is good and .003 is borderline.....above that and a cap is useless. The large "digital" and carbon/hybrid multi-farad units do not work because their ESR is too high.......sure, they store lots of energy but can't discharge quick enough to do any good.....any battery would be better than one of these units. Don't get sucked into the marketing hype of batteries that act as capacitors either.....they still don't discharge quick enough to do what a low ESR cap can. Be careful of digital readouts and large distribution blocks on caps too, sure they are cool and very pretty but add resistance....I always remove mine.....low resistance is what caps are all about.

And to the OP, we need more info about your system before either could be suggested.
 

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There's so much misunderstanding about caps for use in car audio.....whether they are needed, "do I need a cap?", "caps don't work", "get a battery instead", "do the big 3", "buy an alternator", "I have a cap and my lights still dim"...etc

First, don't get a cap to fix dimming lights.....although they sometimes can fix this. Caps aren't a battery, they aren't an alternator and they don't create any voltage, nor are they a replacement for "the big 3" .........they work in conjunction with any and all of these and act as an energy storage buffer to instantly(faster than any battery ever could) supply this energy to your amps during large transients. If your system constantly exceeds this energy buffer then you need to beef up the weak link in the chain elsewhere in your electrical system.

Not all caps are created equal.......stay with the 1 farad canister types and your usually pretty safe, the rule of thumb is 1 farad for every 1k watts. What makes a cap desirable for car audio is it's ultra-low ESR(resistance). An ESR of .001 is ideal, .002 is good and .003 is borderline.....above that and a cap is useless. The large "digital" and carbon/hybrid multi-farad units do not work because their ESR is too high.......sure, they store lots of energy but can't discharge quick enough to do any good.....any battery would be better than one of these units. Don't get sucked into the marketing hype of batteries that act as capacitors either.....they still don't discharge quick enough to do what a low ESR cap can. Be careful of digital readouts and large distribution blocks on caps too, sure they are cool and very pretty but add resistance....I always remove mine.....low resistance is what caps are all about.

And to the OP, we need more info about your system before either could be suggested.
Thank you! I didn't want to be the one to type all that out. lol.

Our alternators only do like 40amps at idle, and max at like 80amps at 5K rpms. So if you plan to run a bigger battery, or 2nd battery, your going to need to upgrade your alternator as well. The guy my sponsor deals with for this builds custom spun alternators to meet the vehicle needs. Also to comply with competition rules. He wants to set mine up with a alternator thats cranking 100amps at idle, 180 at 5K rpms. Which is almost triple what the stock one does at idle, and over 100 over the top out on our stock ones.

Proper gauge wire, solid clean grounds and good connections are key to getting your system to sound right. If you only get the 8 AWG wire when you should be running 2 or 4 AWG Wire then your asking for problems.

who ever said 1 farrad for 200-400 watts. You have no idea what your talking about.

Most people get caps because of the pretty lights, and they take up trunk space. This is not always needed. Just spend the money on quality amps/subs, proper wiring, and solid power source upgrades.

I'd also like to add, sealed battery, or capped battery doesn't mean ****. The advantages of sealed batteries are as followed: You can ship them UPS because they are sealed. You can mount them where ever you want how ever you want because they are sealed and don't leak deadly vapors off. They are approved or required by many racing leagues. Most are a deep cycle. So you can run them down more than a normal battery with out killing your cells. They typically don't use magnetic plates anymore. They are typically Cylinder style power storage.
 

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Caps are for regulating small voltage spikes before they get to the amp, batteries are for making up for large voltage drains and major fluctuations.

Caps are not meant to make up for a deficient charging system. Caps will provide a small amount of power very quickly to stabilize the input voltage of the amp and sometimes aid in the musicality an impact of the amp.

They both serve drastically different purposes.
 

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like ur info "Trebor" and "MSIguy", if u think of it ur amps actually have caps in them too. of course they are not 1 farad:) but like trebor stated...in simple terms think of a cap like a cup of coffee with some major kick to give ur car stereo that extra jolt...when needed, especially dynamic parts of ur music ...but in tha old days in car stereo where everyone ran multiple batteries we used isolators...before caps came into play...back then we just used good old deep cycle batteries w/some major cold cranking amps...(back then interstates to optimas, etc)...and oh yes, major alternators back then :)...man, what happened to when we would take out tha back seats and build a wall with a bunch of punch 150's (killer amp back then) with some punch pro 12's lining up the whole back wall :) ..that i remember the G&S redlines subs, mtx terminators and good ole cerwin vegas....love tha old school amps, orion hcca's, extremes, precision power, autoteks, hifonics, soundstream, phoenix gold...oh well thats a whole different ballpark with this old school stuff! much props to u trebor with tha info!
 
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