RApiDArTiFAcTs

When the car is running or off, does the amp draw a constant current from the battery or does the power drawn vary depending on the set of the gain or volume??(the louder the volume, the more power drawn from the battery.)

I just wanna know if I should invest in a capacitor anytime soon.

imported_loudsubz

Car off = no current drawn
Car on, amp being used at moderate level = current drawn
Car on, amp being used, but hardly any volume, = very little current drawn

Capacitors = band aids, dont spend your money on it.

Whiplash

ditto..
imo, couple of remote gel cells and an isolator

RApiDArTiFAcTs

What about when the key is turned to the second position, but the engine is not running?

Approx. how much time would I have before I need a jump or have to start the engine again?

imported_loudsubz

That again depends on how loud your playing your stereo.

More volume = more power needed = more current drawn.

You can get a voltage meter and it will let you know when your volatge has gone down too low and you need to restart your car to recharge the battery.

Theres also isolateors that do this for you, that hook up to the battery and automatically cut off the power when it sense your voltage is getting to low, and gives you enough charge to start your car, but there are drawbacks, because the cable going from the unit to the battery is a small gauge, and limits the amoutn of current you can draw on it, so its only meant for small to moderate sized systems.

Like Marty said, get a few gel cells. Something like Optima Red top, or theres other brands out there, that arnt as expensive, like Hawker i think.

Isolator is good because it wont put as much a strain on your alternator as if you hooked both batteries up in paralell.

Make sure if you run another battery, to get a a sealed gel cell, so when ti charge it wont release the toxic gases in your car, which could cause an explosion if you mount the battery in your trunk.

RApiDArTiFAcTs

Alright, thanks guys. I think I might go with a voltage meter or an isolator(cutoff). I dont really want to go through the hassle of installing another battery in the trunk.

Explosions and toxic gasses dont really sit well with me. :firefight

imported_loudsubz

http://www.sounddomain.com/sku/DAKODY053KT

or soemthing like this

http://www.crutchfield.com/cgi-bin/S...127BA3&o=m&a=0

Issues

for your info.....capacitors......good thing to help smooth out the bass when its up loud...its a great help for the buck and it's easy to install...ave time to drain a battery....@ 45-60 minutes at full throttle with your volume.....isolator+additional battery(gel cell).....great idea but can get expensive....isolators work when the veh is on (not off).....to do this properly everything is usually @ 4awg power wire.... the same guage all the way around......isolator package (half decent one) @ 200 bucks + Optima Deep Cycle Gel Cell yellow to for stereo applications/red top for racing applications..(BTW @ 250 bucks) Capacitor = 200 bucks. you be the judge...i've got a large system in my integra + my EL and both have capacitors.........oh ya btw don't boom your system when the car engine is off........not good!!!!

imported_loudsubz

Capacitors do help a bit, but there realyl overated. People tyhink if they install them all their problems are solved.

Summary of whay caps suck (borrowed from CCA)

1) Even if the cap has low internal resistance, it still has some. The more current you try to pull out, the more it's output voltage will drop. Caps are supposed to provide current to keep the voltage from sagging.

2) Caps don't store very much energy. A 1.0F cap stores 98 joules at 14V. A 65 amp/hour battery stores almost 3,000,000 joules at 12.8V. A joule is a watt per second. The 1F cap could theoretically provide 98 watts for a period of 1 second.

3) 10 volts represents the point where a car stereo can no longer remain operable. If we look at how much energy a cap can provide down to 10v the result is 48 joules. The car battery can still provide 2.5 million. Point here is that 1/2 of the cap's capacity is actually usable.

4) (similar to (1) ) All electronic components have internal resistance. Even if the cap is good, when we try to draw large quantities of current, the output voltage will drop. If we ask for too much current, the cap will do squat since the output voltage would drop below 10v.

5) A 9v battery can do 20x more work than a 14v/1.5F cap

6) In real world tests with a 2kW stereo, power-on listening makes a big difference in residual voltage compared to power-off. Cap has an insignificant impact. Average voltage remains at 12.xxx whether the cap is in or not, not 14.xxx as some would assume.

Furthermore, as the stereo draws more current than the alternator can produce, the voltage will drop. The Cap will attempt to supply 14v at the requested current level. Chances are if the Alternator is not able to keep up, the draw is large. The cap will suffer internal resistance and do squat. The battery will begin supplying current at 12.x volts and will continue to do so due to its millions of joules. Ironically, when the musical peak is complete, the cap will present a load to the battery/alternator.

7) The amount of caps necessary to achieve a satisfactory amount of joules with a low enough ESR is 15+, regardless of size. The combined ESR shrinks when these devices are in parallel. 15 caps cost more than a good battery or two.

8) Factory alt/battery is adequate for a 2kW stereo.

Moral of the story: Spend your money on a battery with a low ESR. This will help the battery to supply current without as much of a drop in voltage. Caps look good in your car but do very little to help your stereo. Headlights dim because the alternator experiences ESR drop when it tries to supply max current. A cap can help with this but it actually increases the load on the alt. ESR comes into play during charging as well.

Issues

now that we've completely confused our friend.....I hope that you understand what you just re-published......cause right now ......it seems likew the blind is leading the blind.....the caps take care of the immediate demand for power when voltrage does become drawn and te alternator cannot compensate immediately....the cap supplements.....the original question may have confused you...our brother was playing his stereo while the vehicle was off...problem #1............as I said..........dude that's not good........deep cycle gel cell or a reactor gel cell only have a dry reserve of approximately 2-2.5 hours then the recharge has to take place and w/o a beefy alternator either way your up ***** creek!!! problem #2 our reader was confused over the purpose of a capacitor.....advice....Keep It Sweet + Simple!!!!Problem #3 our reader probably sounds like he's got a very basic system that doesn't require a second battery.....most pragmatic way of tackling his request.....Capacitors---->>>>>best bang for buck to provide smoother bass!!Finall..... problem #4........................ Dude please tell me that you don't run your system down to a 10 volt load...otherwise .....I suggest you should go over that little publication you just re-wrote!!!!Oh ya BTW explain digital capacitors with voltage meters mounted to the top of the capacitor are they suffering from "internal resistance"......hope to hear you someday.....then again I probably won't !!!

imported_loudsubz

imported_loudsubz

Proove me wrong, but from what I read, capactiros are overrated. They will help, but people think there a fix for everything.

Issues

got 147 dbls to prove you different..........from a high current amp.


once again.......love to hear you later but iprobably won't...


Sound off any one?????


Oh ya still ..........

imported_loudsubz

147 db's from what setup. Box size/Car/Port area/wattage etc.

What amp. Have you experimented, tried using larger gauge wire, upgrade ground from frame to to battery, alt to battery??

Tried putting a gel cel battery before your amp?

Issues

225 HCCA
Lil wonder 4
0 -1 awg front to back (pos + Neg ground)
4 awg fr distro - amps
Experimented---------->maybe even install for the past 10 years!
BTW 12 different ground points in vehicle all at a min 4 awg
1 optima deep cycle yellow top gel cell
3 lightning audio 1.5 farad caps
130 amp modified ambulance alternator
and a whole lotta noise!!!


Fusion...........izn't it?



PUL OVR.........izn't it?


I'm still

cause u gotta be @ the wheel!

you said something ......did I hear a tiolet flush!!!

imported_loudsubz

Im glad it worked for you, im still sticking to what I have read, and seen others test.

Im not tryign to start a war, so I donno why your so on my case, im just trying to give my point, thats what the boards about.

RApiDArTiFAcTs

Whoa, come back to my thread after a day and beef breaks out.

Basically I was just looking for something simple to play my discs at a very low volume when the car is off.(an hour max.) My sys is just a 45x4 deck, and 200w RMs amp.

I know you said not to "boom" my sys when the car is off, but I wouldnt do that. Just curious what are the negitive effects of this besides a dead battery?

I was only considering a cap, because it was to my understanding that it stores power when your battery gets low. And for a 500w amp, even a .5 farad cap would suffice. The gell cells and isolators seem like I would need to change my major to electrical engineering to decipher, but I would definately look into it, if it was more logical to me.

Im getting two strong opposing sides here, third party intervention???

imported_loudsubz

Im sorry If i went out of line. I think I read your post wrong, and didn't provide the info you neded. But now that we know what your situation is, and what you want, I still belive you should upgrade the battery under the hood, to an Optima, or Hawker or the like (plenty of other brands that are the same battery as the Optmia but sell for less)

Stinger makes one that fits in the stock civic battery tray I belive too.

RApiDArTiFAcTs

Loudsubz, so your saying if I upgrade my battery, that'll be enough to get by???This sounds too good to be true.

How much does a Stinger cost??? In stock at Crappy tire??
And how much more power does it provide over a basic battery?

Thanks.

imported_loudsubz

Optima Yellow Top

For your situation, you only want to play your stereo with the key off, at a low level so an upgrade in the battery is a good investment.