95Juan

Ok, so i had a 750watt amp powering 2 12" "1000w" subs. they werent retardedly loud outside of the car, but they were perfect on the inside. they had a nice little ported enclosure with plexiglass on the front (they're kind of blingy, but they sound good, so what the hell?).

so the question comes in- what do i need to do to not make them kill my electrical system when i have music on?

i had them for a while, and they would just rape my electrical system. even if i had it turned off completely, the voltmeter in the dash would fluctuate so bad. it'd go from ~13, and then in literaly half a second, peg itself at the top of the meter. then normal again, then entering the red, then pegging again.

i havent run the subs for maybe a month now and the electrical system seems to have evened out (constantly at ~13, drops to ~12 at night with full lights).

i'd like to run them again, but i know it'll just go back to that craziness.

i know it's caused by the subs and the big drain that they have, but what can i do to make them.....not kill it?

is it a battery problem or an alternator/VR problem?

i've been thinking about getting a capacitor or something, but i really dont even know what the hell that does, aside from it says it saves the electrical system.


i know there's some electrical/audio guys on here that can help, so any info is appreciated.



TIA.

PCinDC

A capacitor stores a charge for conditions where a sudden discharge is required. The 1+ farad units used in car stereos are made to power a driver in the event of a sudden high demand (i.e. when your subwoofer hits 10Hz and the volume is up.
A capacitor will help to a degree, but if you are having drastically fluctuating voltage, you should take a look at the voltage regulator on your alternator. Alternator shops can work on our alternators, nothing special about them.
You can also get a BatCap, which is part battery, part capacitor. You will want to run an isolator if you do this or the batcap and the battery will be in a constant push/pull, draining your battery over and over again.

95Juan

so a 1+ capacitor would be good for occasional use? I only use the car friday-sunday, and half the time, i'm not even using the stereo that much. when i first brought the car home from the stereo place, i was blasting it so loud that my St. Christopher medallion on the rear view was actually jumping, and admittedly, i did get into one or two stoplight showoffs with some "mackin pimp" or something, but 80% of the time it's for my enjoyment, and i dont need it to destroy my head.

bearone

use a decent dvm on the batt terminals.

check voltage not running, then running, then add a/c, lights, amp, and check the voltage at each progression.

12.6 v is what you should see with no load on the batt, after sitting overnite.

if you see 12.7 v with everything on, in that hi load environment, day in, day out, the alternator will die prematurely.

they're not built to run at the max all the time.

87951

Bill.e1

Where are you pulling the power from? 750 watts out is probably close to 1000 watts in or around 70 amps. You need 8 gauge wire min, 6 gauge is better. Your car should have a 115 amp/ 1600 watt alternator and a 15.0 wire (about 7 ga.) to the starter. From there a 35 (~2 ga) wire goes to the battery.

At 70 amps, a .1 Ohm connection resistance will drop seven volts. You need perfect connections and a six gauge straight from the battery to the amp. You can use a voltmeter to check voltage walking back to the alternator to see where the voltage is lost. Since you are seeing the voltage drop on the voltmeter, it probably isn't a ground issue.

Caps can help as would a fresh battery or even a second battery- a big one. You may want to limit current from the main battery to the secondary. This way, if the pull exceeds capacity, you will get distortion, not fireworks.

Hope this helps,
Bill

jacklet

i had a similar prob. if your cables are still oem replace them esp the grounds next check the alt. to starter connection and make sure it is good. maybe have youre alt. checked by a shop that re-builds them and make sure it's output is correct. how are you connecting at the bat. caps only store power for peak periods when output is at its peak, these cars are notorious for elect problems.