Help me please!!!!

Ok, so ive got:
2 12" Power Acoustik Fubr's DVC 2 ohm
1 Gage rockford wiring with 300 amp fuse
2 High performance rockford RCA's
1 farad rockford capacitor
Power acoustik A3000DB Digital Mono Amp w/ remote
Pioneer 2-channel Amp
Pioneer DEH-P7600MP Head Unit
Sony front 3x5 speakers
Pioneer rear 6x9 speakers
( soon ) Alpine tweeters

Whenever the bass hits hard, the lights dim and i can only imagine how hard this is on the alternator. I was told i could buy a yellowtop battery and another larger cap to fix this. Do you think i should go with a high performance alternator or a cap+yellowtop battery? Keep in mind that i don't have much money to spend at all... I think my stock alternator is 80 amps...so obviously i need to do something fast. Hook me up with some ideas, thanks!

Oh, and i've read that some of you have said not to get a capacitor with a voltage gauge on top???? I dont have one, but i noticed they are cheaper so they caught my attention.

Check your cap to see if its wired right, I had a 1/2 farad on 2 L7's with a Kicker 1200.1 amp and nothing dimmed. If its wired right, you can either:

1. Get one bigger cap
2. Get another cap and add it to your current one
3. Get an optima yellowtop battery
4. You could buy a better alternator, or you can have your current one rewound, that might be a little cheaper with the same effect

You prolly only need to do one of the above, not all 4, so get some more opinions and see what's most economical(second cap is probably most economical).

Wow, thanks. Yea i've heard of people getting their alternator's rewound, i havent heard how much it costs of what the affect is. I figure since ive got a week one anyways, that i should just leave it and get a yellowtop battery because they are only $150. I really don't want to ruin my alternator.... And a 2 1/2 farad cap was around 300$, but i'd probably spend that if i knew that my car would be safe. So you were saying that you think i should get another larger cap?

Get one big cap(2farad should be fine) or just add another 1 farad. Look on ebay for caps cuz you can find like a 15 farad for dirt cheap. Places like bestbuy charge $100 for 1 farad and $150 for 2 farad, the pricing is illogical and overpriced to begin with. You can get a yellow top batttery and another cap for under $300 easy.

screw another cap, if one isn't doing anything for you then why do you think a 2nd would? Upgrade the magic 3 and take a close look at your gain setting. A yellowtop will help, a 2nd or replacement cap will do nothing, and a new alt will make the dimming worse at idle and low rpm.

screw another cap, if one isn't doing anything for you then why do you think a 2nd would? Upgrade the magic 3 and take a close look at your gain setting. A yellowtop will help, a 2nd or replacement cap will do nothing, and a new alt will make the dimming worse at idle and low rpm.

Ok, i cant tell if the magic 3 is something or another word for soemthing.... lol, im a noob. So in other words, what the hell is it? :iceslolan I would think a yellowtop and another cap would do alot...and thats only 300$.

( Gain: 3/4 )

Whatever works as long as i don't have to worry about ruining my alternator!

don't get another cap, upgrade all the wiring, the ground, power wire, all the good stuff

Yea, i just had that done. The wirings all rockford and 1 gauge... And knowing the alternator's only 80 amps, i think i'll just go with a optima yellow top battery. Anyone think of a better idea? Basically the best thing i can do for under 300$. -Thanks

Also, what type of optima yellow top would i need for a 1994 Ford probe? I'm gonna hit up ebay i think.

Hey, i was just lookin on ebay and saw this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=50547&item=5713849468&rd=1

Also: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=50547&item=5713845536&rd=1&ssPageName=WDVW


I noticed it was cheap, but if it works... Do you think that would be a good add on to help dimming and strain on the alternator? I'll still get a optima yellow top if you think i need to. Let me know asap!!!! Thanks dudes!

isn't it just another thing for the alternator/battery to charge? i don't think it will help..........it might, but i couldn't tell ya, i don't use caps, and never will.....

Hey, i was just lookin on ebay and saw this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=50547&item=5713849468&rd=1

Also: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=50547&item=5713845536&rd=1&ssPageName=WDVW


I noticed it was cheap, but if it works... Do you think that would be a good add on to help dimming and strain on the alternator? I'll still get a optima yellow top if you think i need to. Let me know asap!!!! Thanks dudes!

damnit stop looking at caps!

lol, I don't mean to be harsh (well I kinda do, to get the point across), but if you have a cap now and it's not helping, why do you think adding another one would help?

the magic 3 is upgraded wiring under the hood, sort of like 1/3 of a grounding kit you can buy from hks or whatever. Specifically, you upgrade the batt - to ground, engine to ground, and alt + to batt +. You don't have to replace the stock wires in these locations, you can just add to them (more wire means less resistance which means it helps more). Use 4awg, anything more is just overkill and you won't notice any improvement.

Upgrading the magic 3 will give you at least as large of an improvement in dimming as a cap will, but it costs like $10

lol... thanks, i *think* i get the point now :iceslolan
Ok, well i don't know if i would be capable of upgrading that stuff...
I dont even know where the alt is... lol
Anyt directions somehwere like in detail? or do you mind explaining this to a noob? Im getting a optima yellow top anyways. thanks dawg

I know it might sound intimidating, but it's really very very very easy. Here are some instructions
1 - find one of the 3 cables you're going to upgrade
2 - take your cable, put a ring terminal on one end
3 - lay your cable out right next to the stock one, so it's like a mirror image of it
4 - mark with your finger how long it needs to be
5 - cut it to that length and put a terminal on the end
6 - bolt it in place right next to the stock wire
7 - go back to step 1

The alt + to batt + is the only one that's a little more complicated, but honestly you can go without doing this one for a while if you don't think you're up to the challenge. The engine and batt - grounds are the easiest though, couple minutes of cutting, stripping, and pounding terminals onto the end of the wire and you're done.

2 12" Power Acoustik Fubr's DVC 2 ohm
1 Gage rockford wiring with 300 amp fuse
1 farad rockford capacitor
Power acoustik A3000DB Digital Mono Amp w/ remote



With a 1 ohm load (dual 2 ohm speakers) you will be hitting more than 90 amp straight draw off a 500w RMS amp. You'd need more than a 20 farad cap just to stop the voltage from dropping to 10v from 12v with perfect ground.

Your lights will still dim off a yellow top @ 13.6v without the cap. Save the money on the battery and buy the 300$ 50 farad cap, with 1ga wiring your lights wont dim even at idle(barring rap music =).

those r just estimates but you can do math to get the exacts. the cheapest way IS the cap

Holy shit, really? I've never heard anyone using that much.
Ebay: 50 farad for 300$ yea. i was just gonna hit up the power acoustik 5 farad for 100$. You sure i need 50 farad? Well around that. But yea, its 3,000 watts at 1 ohm, which i have it at. Gains: 4/5. Damnit i don't know what to do. Ya'll say somethin different. With a HUGE cap though, would my alternator be good?

50 farads, thats crazy power. 1 farad equals 1000 watts power(so they claim) I highly doubt you'll need 50,000 watts power. Watch out for the ebay caps, I bought one for $150(5 farad), it's a piece of shit(Lanzar), no way that it could put out 5,000 watts. You should be fine with a new battery. If you do wanna get a cap as well just to be safe, 3 farads seems more than enough.

50 farads, thats crazy power. 1 farad equals 1000 watts power(so they claim) I highly doubt you'll need 50,000 watts power. Watch out for the ebay caps, I bought one for $150(5 farad), it's a piece of shit(Lanzar), no way that it could put out 5,000 watts. You should be fine with a new battery. If you do wanna get a cap as well just to be safe, 3 farads seems more than enough.

Do you understand what a 1ohm load is? do you understand the difference between a battery & capacitor? do you know that the crappier the amp the MORE power it requires?

OK, take a step back - do you know how electricity works?

With a 1 ohm load (dual 2 ohm speakers) you will be hitting more than 90 amp straight draw off a 500w RMS amp. You'd need more than a 20 farad cap just to stop the voltage from dropping to 10v from 12v with perfect ground.

Your lights will still dim off a yellow top @ 13.6v without the cap. Save the money on the battery and buy the 300$ 50 farad cap, with 1ga wiring your lights wont dim even at idle(barring rap music =).

those r just estimates but you can do math to get the exacts. the cheapest way IS the cap

um, no
a 50 farad would have an internal resistance so high that it would be useless.

"the cheapest way is the cap", I'm sorry but that's the funniest thing I think I've ever read

um, no
a 50 farad would have an internal resistance so high that it would be useless.

"the cheapest way is the cap", I'm sorry but that's the funniest thing I think I've ever read

Have you even used a 50f cap? they are 10f caps in series in a big box linked by a solid steel bar... so the resistance isnt much different from a 1f. go do a lil research, or betta yet - buy one.

Holy shit, really? I've never heard anyone using that much.
Ebay: 50 farad for 300$ yea. i was just gonna hit up the power acoustik 5 farad for 100$. You sure i need 50 farad? Well around that. But yea, its 3,000 watts at 1 ohm, which i have it at. Gains: 4/5. Damnit i don't know what to do. Ya'll say somethin different. With a HUGE cap though, would my alternator be good?

Think of the faucet running into the palm of your hand(water being current) - the strength of the water flow from the faucet would be what kind of alternator you have, with a stock - assume you have a trickle=)

then take a straw and drink the water(the straw being demand on power from your amp).
If you suddenly wanted an extra boost of water(being a bass note),
you would be sucking half air because your palm would empty of water(air being no electricity making your lights dim)

Then think of adding a small cup like a dinky 12oz can of coke(a 1 farad capacitor) This would allow you to suck a little bit more watter without running out, you will still run out though, most amps draw much more than a 1f could supply, a single 1f is more for the amps benefit than the alternators(it will increase sq).

NOW think of a 72oz Big slurpie cup from 7-11, this would be a 50 farad capacitor. Depending on the size of your straw(the amp)
you still might suck it dry, but isnt that a LOT more water to suck before it runs dry?

The purpose of the cap is to dampen the peak demand on the alternator hence reducing(if not eliminating) the light dimming and taking some of the load off the alternator. The same amount of power must be produced by the alternator & batt, all the cap does is give the alt & batt extra time to reproduce the power while it supplies the current to the amp. Since there is no immediate requirement for the current, usually the battery will recharge the cap before the alternator.

50 farads, thats crazy power. 1 farad equals 1000 watts power(so they claim) I highly doubt you'll need 50,000 watts power. Watch out for the ebay caps, I bought one for $150(5 farad), it's a piece of shit(Lanzar), no way that it could put out 5,000 watts. You should be fine with a new battery. If you do wanna get a cap as well just to be safe, 3 farads seems more than enough.

How do you know that "theirs no way it can put out 5,000 watts"? Test it? The 50 farad LANZAR is only 240$, so even if it is half effecient its still 25 farads for 240. Not bad. And i'm assuming its more then half effecient. If i'm buying a cap, i myswell buy a large one, rather then spend 150$ on a good 3 farad or whatever. Why waste money. I'm going to hit up the lanzar 50 farad cap, and the optima yellow top battery for about $400. Anyone think, actually, does anyone KNOW of a better way or if this is dumb?

Have you even used a 50f cap?
No I haven't, because I have a 2000rms system and I get 0 dimming on the stock 80 amp alternator and battery with no cap at all.

they are 10f caps in series in a big box linked by a solid steel bar... so the resistance isnt much different from a 1f. go do a lil research, or betta yet - buy one.
I think you mean parallel, since the capacitance doesn't add in series, and even a 10f cap has an internal resistance much too high to be very effective



Think of the faucet running into the palm of your hand(water being current) - the strength of the water flow from the faucet would be what kind of alternator you have, with a stock - assume you have a trickle=)

then take a straw and drink the water(the straw being demand on power from your amp).
If you suddenly wanted an extra boost of water(being a bass note),
you would be sucking half air because your palm would empty of water(air being no electricity making your lights dim)

Then think of adding a small cup like a dinky 12oz can of coke(a 1 farad capacitor) This would allow you to suck a little bit more watter without running out, you will still run out though, most amps draw much more than a 1f could supply, a single 1f is more for the amps benefit than the alternators(it will increase sq).

NOW think of a 72oz Big slurpie cup from 7-11, this would be a 50 farad capacitor. Depending on the size of your straw(the amp)
you still might suck it dry, but isnt that a LOT more water to suck before it runs dry?
And a 50f cap that costs $300 will do this better than a 2nd or even 3rd battery how?

The purpose of the cap is to dampen the peak demand on the alternator hence reducing(if not eliminating) the light dimming and taking some of the load off the alternator. The same amount of power must be produced by the alternator & batt, all the cap does is give the alt & batt extra time to reproduce the power while it supplies the current to the amp. Since there is no immediate requirement for the current, usually the battery will recharge the cap before the alternator.
A capacitor will do nothing for the load on the alternator, if anything it will increase the load on the alternator because as the current flows in and out of the cap some of it gets burned up as heat and then all the current that leaves plus all the current that gets burned up has to be replaced by the alternator. And before you say "but the cap does the quick draw and spreads out the load on the alt over a longer period of time", that's what the battery does, and it does it quite well.

Anyone think, actually, does anyone KNOW of a better way or if this is dumb?

YES
jesus I spent the entire first place going through it, why does no one listen to me?

you also need to lower your gain, unless your gain range goes from 10V-.2V and your headunit has 1V preouts, 4/5 gain is much too high. There are tutorials online on how to set your gain properly with test tones while listening for clipping, follow them.

Ok... Well you have to admit cap's do help SQ in most cases. Might not be easier on the alternator, but will be better when your amp demands alot of power at high volume. Well no need to argue, just tell me what i should do. Get a 200 amp alt? I dont really want to spend more then 300$... And i also dont want to ruin my stock alt... help me!

Ok... Well you have to admit cap's do help SQ in most cases.

Then why do very few competition sound quality cars use caps? They're used in show cars extensively, but you rarely see them in sound quality or spl competitions

Yea, my gain is at a little less then 3/4 now, i tested.

yea you told me to "upgrade the magic 3". Well i dont see how that would the alternator much. And i dont want to mess with that stuff cuz like i dont know where the alt is, or where the engine ground terminal is or whatever so...

Well, they use more batteries. Kind of the same thing. But whatever ok... Just try to help me out rather then argue, you're probably right anyway. Ive only got a 1 farad cap now, so i know i should get a bigger one anyways. So your saying, uprade the magic 3, larger cap, and maybe the yellow top?

Well, they use more batteries. Kind of the same thing. But whatever ok... Just try to help me out rather then argue, you're probably right anyway. Ive only got a 1 farad cap now, so i know i should get a bigger one anyways. So your saying, uprade the magic 3, larger cap, and maybe the yellow top?


only the SPL guys use more batteries and that's because they compete with the car off, the SQ guys use an upgraded battery, alternator, wiring, and that's it.

anyway, I'm getting argumentative because this guy's telling you to spend $300 on a huge hunk of metal that just might help that you probably don't even have room to mount anyway, and you're actually listening to him.

I'm saying upgrade the magic 3, sell the cap, and upgrade to a yellow top.

Ok. By the way, heres my car's system.

http://www.cardomain.com/memberpage/658706/5

Well, i might as well keep the cap. I'll get the yellow top, i was going to anyway because i drained my battery a month a go totally so its probably shitty now. I'll go out right now and see what you mean on the magic 3, i still dont think im capable of doing this.

How the hell do you get no dim at 2000rms? I've got a stock 80 amp alt too. Damn....

Ok. By the way, heres my car's system.

http://www.cardomain.com/memberpage/658706/5

Well, i might as well keep the cap. I'll get the yellow top, i was going to anyway because i drained my battery a month a go totally so its probably shitty now. I'll go out right now and see what you mean on the magic 3, i still dont think im capable of doing this.

How the hell do you get no dim at 2000rms? I've got a stock 80 amp alt too. Damn....


Well if you drained your batt then that automatically tells you that you need a new alternator. A new cap will do nothing but make it worse, and a new batt will let you run it longer before the battery runs dead but it still won't cure the problem

Anyway, look at the negative terminal on the batt, there should be a single cable coming off, follow this about a foot or a foot and a half and it'll be attached to a bolt, this is your battery ground. The alternator is the only component attached to your engine that has a power cable coming off, normally with a red rubber boot over where the cable attaches to the alt. The engine ground depends on the car, but there should be a pretty large cable bolted to the engine at some spot (mine's actually bolted to the transmission) and then it bolts to the chassis just like the battery ground does.

And I get no dimming because I upgraded the magic 3, a while ago I wanted to see if it had really done anything or it was all in my head so I removed the battrey ground cable that I had added. As soon as I turned on the first song I was watching all of my interior lights (speedo, seat belt light, dome light, etc) dim. I put the cable back on, and they all quit dimming completely.

K i'll go look now and update. But you were saying i drained my battery i need a new alt no matter what? Then you said like a new battery will drain or something? i Kind of got confused. I dont want to buy a new alt $$$$...

well the only source of power in your electrical system is your alternator, anything else (batt, cap, etc) just holds charge. If you were able to run all those reserves dry, then that means your average power draw is more than your alt can provide. The only way to fix this is to get a new alternator.

What I meant about the batt lasting longer is that it took a while for the batt to run dry before. Your amp was drawing more than the alt could provide and it was slowly sucking the extra current that it needed out of the battery. Eventually this slow draw sucked the battery completely dry, if you were to get a yellowtop it would last longer before it ran completely dry (because it has more reserve), but it would still go dead eventually. No matter how many batteries or caps you get, it will still run dead, the only way to fix that is to get a new alt.

I dont want to buy a new alt $$$$...

A new alt won't cost much (if any) more than that 50 farad boat anchor, but you were so willing to buy that....

Oh. Well heres the case. The battery ran dry because it was before i had my system in. The car was at storage, and i left it on "Acc" :disappoin And so it was totally dead, wouldnt hold a charge that good. Now it works fine and its been working for a month with using the system. Can you hook me up with a site that has a alternator or performance one for a 94 ford probe? I have no clue where to look, i tried though.

I just looked in my car. I saw the ground from batt- to the chassis like 3 inches off the batt... And then some other cable from the - but i couldnt follow it well... it was way under everything and it went into a "tube" with a shitloud of other wires. The tube had a hole and a series of wires came out and attached to some nasty looking thing. No red boot? So im not sure if thats the alt or not. I couldnt see a cable coming off that to a ground.

Should i run another wire from batt - to ground then?

ohhh, alright, I thought you meant the system ran the batt dry

In that case you might not need a new alt. You still might, but it's not a "holy crap man you need an alt right now" situation.

As for the cables, the one that you saw going to the chassis you should definitely upgrade, in my opinion that's the most important of the 3 wires. The other one coming off of the - terminal might be the engine ground, but it's hard to say since it could be anything really. On my car, a single cable runs off the - terminal to a bolt right next to the batt. It's bolted down there, but the cable keeps going (that's like a random bolt in the middle of the cable run kinda) and it runs about another foot where it bolts to the transmission. The alternator is completely separate, it's on the other side of the engine. It looks like this (http://www.autoshop101.com/trainmodules/alternator/altimage/05f.jpg) and on that little shaft that you see sticking out, there will be a pulley attached. On that bolt that you can see in the back right, that's where the cable that goes to the batt comes off of and has the red rubber boot over it. You would run a wire from that bolt to the + terminal on your battery, but to do so you might need to route it through the engine bay, behind or in front of the engine and all that crap.

Ohhhh, alright. Yea i have the same thing, the ground off the batt - has like alot of other wires going by it. I followed it and it connected via a harness to something, but its not to the alternator. I have a book here that shows me where it is and how to take it out, etc. It says the stock one is "high performance" but whatever that means 10 years ago... What cable should i use to ground batt- again? I don't have any cables other then 8 gauge speaker wire.... lol


If you think i need a cap. I'll hit up ebay. They have a lot, so hook me up with a link to a alright quality one. Probably more 2.5 + farad.

tHaNkS

the cable coming off the batt - shouldn't go the alternator, the alternator connects to the batt + terminal, but that cable should be hidden with a bunch of others. That's the one that you can't follow with your new wire, you have to lay that one out yourself, but I would wait until the end to do that one to see if you really need it since it's the hardest.

To do the batt ground, you should use 4awg or larger. You should only need like 2 feet at the most since it's such a short run, but you might want to get a bit more if you want to do the engine ground too. Just like 5 feet of 4awg and 4 ring terminals would be all you need for those 2. Then another several feet of 4awg and 2 more ring terminals and you can do the alt + to batt +.

I don't think you need a cap at all. If you think you really need one, at least wait until after you do this before you order. You may be surprised and find that you don't need to get one, and it's not like you lose anything by waiting (other than just more time).

some alts. are rated at idle power and are closely regulated to maintain that rating. unless you can totally bypass every component used to maintain their +/- tolerances, lowering your charging systems (Z) will still only result in a regulated output.

some alts. are loosely regulated (ratings change with rpm's for example). this is the type that would benefit more from modifications (ie. wiring). For example, if your system is in a car that was originally designed as an economy car, you should realize that certain components were compromised to meet the target price/profit marks.

components like governors, regulators, step up/down transformers, # of coil windings, wiring (and their respective gauges), etc. etc. all of these components (along with a lot of other parts) are opportunities to help turn a modest priced car to an economy car.

These are the variables that makes one solution work for you, but not necessarily for another. basically what i'm saying is the exponentially varied nature of electricity will become more and more predictable (mathematically) with the more components used to control it.

remember your system is as strong as it's weakest link, if your having problems and feel upgrades are necessary, try to avoid spending money to upgrade parts that will not make a noticeable change to your system. this will leave you with more money to upgrade your known weak links.

eveything has been stated more than enough... I just had to sniker at the 2000w RMS with no dim - either ur bs or ur system isnt using half of what that amp can put out.

Alright, i'll wait on the cap then. I'll upgrade the batt- to ground tomorro with 4 awg wire. Where do you get that wiring and the ring terminals? I could probably use speaker wire 4 awg then? Where is the engine ground located? I have no clue what that means, cuz like the engine isnt the electrical system, or does it mean that their is a ground on the engine? After ya'll tell me this, ill update all of it, and if it still dims, ill get a cap. Anyways, thanks alot for all of you who helped. Peace

ground wire should be like right there in the front of hte engine lookin like a weird little wire that goes from the frame to a bolt on the engine. if its 4 ga speaker wire, makes sure its actually speaker wire and also that is IS 4 ga...

I've never seen 4awg speaker wire, actually I highly doubt it's even made. Jesus that speaker wire would be an inch across and could handle tens of thousands of watts.

4awg power cable can be had at any local welding supply store or car audio store

eveything has been stated more than enough... I just had to sniker at the 2000w RMS with no dim - either ur bs or ur system isnt using half of what that amp can put out.


snicker all you want

you're right about not using all of the power, but honestly who can actually handle being in the car with 500rms going to the front stage and 1500rms going to a ported sub? The person who can sit there and take that is a better man than me...

some alts. are loosely regulated (ratings change with rpm's for example). this is the type that would benefit more from modifications (ie. wiring). For example, if your system is in a car that was originally designed as an economy car, you should realize that certain components were compromised to meet the target price/profit marks.

The battery ground is upgraded to keep the voltage from dropping as the current leaves the battery, it really has nothing to do with the alternator or how it's designed/made at all.

How much it helps does vary from car to car, but the differences are based on how efficient the car's wiring is from the factory, not on how the alt is made.

Ok, well i'll update that stuff tomorro with 4awg. Also, i wanted to know if this is how to set your gain properly:

http://www.caraudioresources.com/content/electrical_tips/57/1/

That's the method I use, except I use test tones instead of music. Either will work well, test tones are just easier to hear clipping on, but you have to be careful if your speakers are being overpowered.

The battery ground is upgraded to keep the voltage from dropping as the current leaves the battery, it really has nothing to do with the alternator or how it's designed/made at all.

How much it helps does vary from car to car, but the differences are based on how efficient the car's wiring is from the factory, not on how the alt is made.

upgrading the alternator does affect the performance. the battery will only supply so much power under a peak load, thats where caps come in. alternators supply an excess power all the time, so upgrading the wiring will allow more of that power to reach your amp before anything else.

I didn't follow any of that


What I was saying is that the only current that passes through the battery ground is current that's entering or leaving the battery, meaning the battery is either being charged or discharged. Whether the alt puts out full power at idle or not doesn't really have much to do with anything, upgrading the battery ground will still reduce a voltage drop whenever current is pulled from the battery. The upper limit on the amount of current that a battery can discharge is so high that it's ridiculous, I don't really know what that "the battery will only supply so much power under a peak load, thats where caps come in" came from, a battery can spit out however much current it needs to, several hundred amps if need be. You'll never draw so much current from the batt that you'll reach its upper limit.

oh, ok thanks


I got another 1 farad anyhow. Dirt cheap rockford. Also i upgraded the battery ground with 4awg. Coudlnt find the engine ground. thanks for all of your help.

good move...

I didn't follow any of that


What I was saying is that the only current that passes through the battery ground is current that's entering or leaving the battery, meaning the battery is either being charged or discharged. Whether the alt puts out full power at idle or not doesn't really have much to do with anything, upgrading the battery ground will still reduce a voltage drop whenever current is pulled from the battery. The upper limit on the amount of current that a battery can discharge is so high that it's ridiculous, I don't really know what that "the battery will only supply so much power under a peak load, thats where caps come in" came from, a battery can spit out however much current it needs to, several hundred amps if need be. You'll never draw so much current from the batt that you'll reach its upper limit.

your logic fails at every corner...


1.The current hte alternator puts out at full power will DEFINITELY affect the voltage drop. upgrading hte engine/ battery grounding will give you a larger path for current flow, but with the alternator at full power you have an instant burst of 70 amps waiting already, thats why when you rev your car up and hold it there your lights don't dim as much on bass notes.

2. The batteries surge capacity is severely limited by the time it takes to create such a current (eg. the chemical reaction in the battery that creates the proton / electron chain) Yes a battery could create a PEAK (meaning momentarily) of more than 800 amps, the time it would take to do so would be far too long for any audio aplication without the use of charge capacitors.

3. A standard battery could possibly put out more than 500amps on peak, the the RESPONSE time of the current leaving the battery and reaching the amp is very long. THIS IS WHAT CAPS ARE FOR - They can create the current and transfer it to the amplifier and a much faster rate than a battery. What that means is, when you have just a battery, the current being created takes time to reach the amp, by the time the peak surge is supplied to the amp, the bass note has already passed or entered its reverse phase, which ends up causing clipping(unequal phase). A stiffening cap provides faster power to the amp to supliment the time between when the battery supplies its own peak current - allowing the amplifier to create a longer, and more even stroke to the subwoofer.

If you hooked several hundred amps up to one battery it would explode =(

1.The current hte alternator puts out at full power will DEFINITELY affect the voltage drop. upgrading hte engine/ battery grounding will give you a larger path for current flow, but with the alternator at full power you have an instant burst of 70 amps waiting already, thats why when you rev your car up and hold it there your lights don't dim as much on bass notes.
I never said the current that the alt put out didn't matter, I said that the rpm that the alt put its full power at didn't matter when it comes to what we're talking about

2. The batteries surge capacity is severely limited by the time it takes to create such a current (eg. the chemical reaction in the battery that creates the proton / electron chain) Yes a battery could create a PEAK (meaning momentarily) of more than 800 amps, the time it would take to do so would be far too long for any audio aplication without the use of charge capacitors.

3. A standard battery could possibly put out more than 500amps on peak, the the RESPONSE time of the current leaving the battery and reaching the amp is very long. THIS IS WHAT CAPS ARE FOR - They can create the current and transfer it to the amplifier and a much faster rate than a battery. What that means is, when you have just a battery, the current being created takes time to reach the amp, by the time the peak surge is supplied to the amp, the bass note has already passed or entered its reverse phase, which ends up causing clipping(unequal phase). A stiffening cap provides faster power to the amp to supliment the time between when the battery supplies its own peak current - allowing the amplifier to create a longer, and more even stroke to the subwoofer.
Yes it takes longer for a batt to spit out a bunch of current than a cap, but the difference is very small, not NEARLY as large as you keep implying. If it was indeed so big, then every sound quality car on the earth would have caps filling the entire car, yet you rarely even find ONE cap in a sound quality car. Why is that? Because these people have delved into car audio long enough and seriously enough to realize that caps have no real world use, it's all a marketing hype that the retail stores want you to believe so they can make more money off of the gullible and ignorant. There have even been tests done showing that caps made very little difference in the actual voltage the amp was receiving. For the price of a cap, there are so so so many things out there that will affect your sound more, hell just about anything you can do will be more useful.

most "sound" cars are really SPL systems ... and caps will NOT help max bass. Bass is loudest when the dynamic range of the signal is very small and it is heavily clipped ....... caps work better with signal that have a high dynamic range (real music). What makes caps effective at all is that amps don't pull staright DC, they pull pulsed DC at like 60KHz - far too high of a frequency for the battery to supply, but easily possible for a cap with low ESR. As for power draw, remember that the battery is a LOAD (not a supply) until the voltage sags to the battery's float voltage.

Be careful of "upgrade" alternators, some of them put out less amps at idle than the stock one.

k.. i upgraded the engine/batt ground. Dim isnt as bad i dont think. But still, if i have the bass bumpin at idle, my rpm's go from 700 ( idle ) down to 350 then almost dies, then up to 900. I think i'm going to increase the idle to 1000 rpm's.

What makes caps effective at all is that amps don't pull staright DC, they pull pulsed DC at like 60KHz
stupid switching power supply, I always forget about that

remember that the battery is a LOAD (not a supply) until the voltage sags to the battery's float voltage
well, if the battery stayed at a constant 12.5V and could not be charged any higher (if the world was perfect and everything that was theoretical actually applied in the real world) then that would be an issue, but batts can build up a skin charge at 14V+ that can last for some time, so if the amp isn't drawing all that much current over what the alt can produce then it can draw from the battery without the system voltage dropping below 14V. I can turn off my car with the system playing and it will take several minutes before the voltage even drops below 13.0V, at least 3-4 minutes before it drops down to 12.5 with the system at a reasonable volume. With it cranked it will drop down to 12.5 within 10-20 seconds or so though.


as for the rpm dropping, the only real explanation I can come up with is when you put such a high draw on the alt, it loads down the engine considerably, and if you have a small engine it can drop down the rpm a bit before the idle controller can react and raise the idle back up. Not sure what to do to fix that though, other than raising the idle. If you do this though make sure you read the haynes manual and figure out how to do it the right way, don't just tighten up the throttle cable until the idle rpm goes up to 1000.

damn, the genious has spoken. yea, i somewhat understand what your saying... yea i've got the manual, and im going to raise the idle to 900 tomorro. All u do is turn a bolt with a screw driver...easy enough. thanks for all your guys help.

yea, the alternator turns mechanical enrgy into electrical energy .... so it saps horsepower from your car when you are loading it down. If it's the factory alt, most cars have a "program" that change the idle to compensate for the additional load but it may not be enough if the alt is small and the draw is large.

I have a rewind shop at work, and we use it to get more power from the same old generators and motors without having to buy bigger more expensive equipment. it's the same concept for your alternator, if you can find a rewind shop in your area it might be worth it to look into rewinding your alt. or even adjusting the brushes will make a little bit of difference

I'm curious as to why my 94 probe takes so long to start. Before i had this system, it would start after a crank or so, now it cranks for 10 seconds, and then once started, it almost dies and then jumps to like 1100 rpms, and the stereo isnt on. Its not an idle issue, or an engine issue as it just started. The idle is 850 rpms. Could it be the alternator on its last days of its life? shitty........ :screwy:

it may be because your battery is always discharged to some degree. Try putting it on a battery charger over night if you can and see if it helps

What I think your problem may be, is that your system wants more than your alt. can give and so it's taking from your battery. Your stock charging system, even though that's the way it's supposed to work in that situation, cannot keep up with the new demands from your car.
I'm not suggesting this as a solution, but this is what I did when I had that same problem on my '86 Supra. What I used to do was cut the sounds off before I started to park, and then made sure my ammeter read about 12-14 volts by revving the engine once or twice before I cut the engine. Another thing you can do is check for grounds. Even if it's small and barely making contact, that's enough to trickle your battery down to that slow starting area...