elclassico

installed a cap to 1 amp that powers the subs. i did this to stop the lights from dimming. the interior, tailights, headlights mostly. after install, they still dim. i am running the stock battery. i was thinking maybe the ground from the battery isnt good enough? anyone mod the bat. ground? or i was also thinking of getting an optima battery? anyone have experience with this. i did a search but mostr revolve aropunf the argument of its usefullness. please offer any help, its a tsunami cap 1 farat. any suggestions

elclassico

bat +. to cap +
cap+ to amp +
amp - to cap -
cap- to ground

i checked it with a volt meter, and it holds energy, so its weird that the lights still dim?

ROLNLEX

what size amp? also, what're your battery specs (meaning cold cranking amps and cranking amps)? A high amp battery will do fine....maybe have your alternator and battery tested. Also...a low quality cap will sometimes still allow the lights to dim... just my 1 1/2 cents

ROLNLEX

You posted at the same time as me
If I am wrong, someone please step in and say so...but I think you should ground your amp and cap seperately with as short a ground wire as possible. I don't know why...I was just told this once upon a time and it's how I've always wired my systems

elclassico

the wiring is fine how it is, i was told, i did try them both ways same problem. but its better to have the amp pulling of the cap completly, hence grounding the amp to the cap. i tried the other way already and same problem. the battery is stock from a 2000 gs. the amp is only 300w. i was also told all caps are virtually the same. testing my battery and alternator? maybe, anyone know how to do that? please help, i may just return this cap, i got it from circut city, tsunami? i was told its decent? anyone with a gs who had a light diming problem that they resolved with a cap? i was also told even if my lights still blink the cap is helping? but theres no point in keeping it if i bought it to resolve the dimming problem? keep the comments coming pelase!

koreanpers

Hi ppl. I was a car stereo installer/security installer for almost 4 years. You should wire the cap in the following manner.

Batt to capacitor. Capacitor 12v to amp 12 v. The negative from the cap goes to ground. The Negative from your amp goes to ground. Do not connect your amp negative to the cap negative.

What brand cap did you buy? Put it this way, you need more than 1 cap to solve the dimming problem. i know they say that 1 cap for 1000 watt system..but that is not true.

Also, what gauge wiring are you using? You should be using at least 4 gauge...i prefer 2 or 0 gauge.

In our BMW, i have 4- 1 farad caps (Rockford Fosgate Digital Capacitors) and 1 JL 500.1 AMp w/ 1 JL 12w7. Our lights barely dim now. Before, i had 2- 1 farad caps..and the lights still dimmed. I have come to the conclusion that you need about 4 -1 farad caps to solve the situation Now, the GS4 is gonna get hooked up closer to spring...and i will be using at least 4- 1 farad caps

Well, hope this helps. Feel free to ask away

elclassico

i think its 8 guage wire for the cap and the amp + and -. so i got the battery and alt tested, everything is fine. what kind of battery do you have in the bmw? also tried to wire it both ways, no difference. but i think its better to ground the amp to the cap. its preference but the ground has polarity, either way i tried same problem., its a tsunami cap, nondigital. ive heard the digital isnt needed? so 4 caps? geez, i only have a 300 w amp and 2 12'' woofers. before i get 4 caps im going to get a red top battery. but helpful info, maybe 1 cap isnt enough. especially with the lex. alot of extra lights exterior and interior? any other thoughts? so maybe i should just keep it? or get 1 more and a new battery? hhhmmmm. . . .

elclassico

so anybody that can recomend a good make? maybe something made in usa? i think this tsunami is made in taiwan. als any info on those 3 farad or 6 farad capacitors? digital vs. non digital. i know digital only refers to the display and it uses power to run the display. any input would be cool..

ROLNLEX

Okay, I won't lie...I've never been a professional installer or had any professional training. I have read alot, talked alot, and installed alot though. I'm not calling koreanpers out or anything, but I don't think putting 4 one farad caps on a 300w amp is an efficient use of space, money or effort. If your alternator had been generating low then that would have been your problem. I would say your battery though...get a battery with a high cca (cold cranking amp) and ca (cranking amp)...the cca is how much power is available to start your car (or to pull from the battery when the car isn't running) and the ca is how much is available with the car running and the alternator backing it up. Optimas have really high cca's and is great for running a system when your car is off (also good as a back up battery with the huge systems). Buy the highest cca and ca battery you can find and it will still be cheaper than the red top. There is nothing wrong with an Optima of course, just giving you more info to go off of. Also, the quality of the cap is def. and issue...if it's not an efficient setup (internally) then it won't release power as quickly. That's why your car lights dim...not enough power available in an instant to supply the pull of the amp (even at only 300w). A one farad cap is plenty and your 8 ga. wire is fine also for that size amp. Just maybe get a more quaility cap and def. a better battery....lightning audio makes great caps...so does PPI and Rockford. Digital display really don't matter at the size of the amp you're running either. Again my 2 cents and if I'm wrong anywhere I know someone will correct me...haha.

elclassico

thanx for the reply. i will do something soon and post results, i think i m going to return the cap. ???

koreanpers

Hey no worries, maybe i should be more specific. When i was talking about my setup w/4 caps..i was not meaning that he needs to get 4 as well he should get 2 total. 2 should be fine. Also, 8 gauge power wire is not sufficient. You need to use at least 4 gauge. Why? Because the 8 gauge doesnt allow enough juice to the capacitors. Believe me on that part.

As for the battery in our bimmer, i didnt upgrade that at all Now in our gs, i am using 2 caps w/ jl 500.1 and a jl 12w7. The lights dim but not near as much as when i only had 1 cap installed. i have 2 more caps waiting ...but im gonna install those when i do the whole system install

Also, digi caps are not necessary, they are more for show

koreanpers

also, not all caps are made alike. Of all the caps i have gone w/ - stinger, rockford fosgate, streetwires, etc, i really like the rockford the best to date. You can get them realatively inexpensive on ebay...just do a search on 1 farad fosgate caps

ROLNLEX

I agree and running more than one cap will help...two is way better than 4! hehe... if you're going to run two, a higher guage wire would help charge the caps. Anyways...one 200-300 watt amp really shouldn't even require a cap with a good battery and charge system. My girlfriends civic (I know, I speak blasphemy in the Lexus forum...hehe) is running a rockford 300w with two rockford 10's and the lights don't dim...but she has the highest amp battery we could buy and the levels are adjusted properly. ( I know you probably have your levels adjusted right, but maybe turn down your gain and draw a bit....that will def. help) More gain doesn't always mean better sound! Thanx for not getting offended koreanpers!

koreanpers

yea no problem! see, i never have upgraded the battery, i always have just used the stock battery. Upgrading the battery should help as well. Yea, i dont have the gain all the way up

jmecbr900

I'm gonna chime in here for a sec.

You do not need a bank of capacitors to remedy this problem. A bank of capacitors is only needed when you have a big amount of juice needed to run the amps right, i.e. ultra low impedence, running multiple subs off a single amp (more than 2), etc. If you are running proper gauge wire back to the amps, ground properly, and not overdriving them, you will be fine with a proper size cap to relieve dimming issues. Always remember that dimming interior lights is very easy to do. The bulbs are very small and a variance of .1 volt will make them dim. Where you have to be carefull is when you are pounding the sound system and not letting the alternator charge the battery, so you are constantly draining the system.

A capacitor is designed to charge and discharge ultra fast. Many more times faster than our conventional batteries, even Optima batteries. The capacitor will discharge it's voltage to the amp when the power needs arise, i.e. bass notes. The capacity of the cap will determine the amount of voltage it can put out. This is measured in Farad(s). The amps efficiency and/or how it's wired to the spkrs will determine how much voltage it will draw. Some amps draw little current when wired in stereo, but will double when bridged or mono.

I would personally use bigger power and ground wires first. Then, I would make sure that the amp ground was in a good and sturdy location. BTW, I too think you should wire the amp by itself and not to the cap. You can never had too much good ground. I would then make sure the amp was wired properly to the subs. Finally and only then, would I go and hook up a cap to try and help the situation. One 1 farad cap should be plenty for a good 300w amp running a pair of 12's, as long as everything else was in place. If you have small wire, bad grounds, or running the amp too "hot" a cap is not going to save you.

BTW, a cars battery rating is not necessarily going to mean anything in stereo terms. What does matter is first off the condition of the battery (i.e. is it working properly and properly charged), and then the battery's ability to replenish itself. Conventional car batteries use a combo of lead plates and acid to maintain it's charge. It is an efficient enough method to START a car. Optima batteries use a different method. It is more efficient at charging and discharging itself, similar to the capacitor definition above. The reason why Optima batteries are widely used in stereo cars is not because they are more powerful than conventional batteries, it's because of the battery's ability to take the abuse of constant charging and high current demands of a stereo system and it's ability to recover from that. You will still need enough juice coming back to maintain it (alternator), so if you drain it down to nothing and then don't give it enough time to recover back to full charge and just beat on it you will kill an Optima battery too like any other.