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I have 4 jbl 1000 watt 12 inch subs and 2 500 watt jl amps, along with a 7 inch flip-out head unit. When I drive at night with the music loud all of the lights dim when the subs hit, and when I turn it down no flicker or anything. Could this just mean I'm overworking the battery? I plan on adding Hidx lights in the near future, should I add another battery?
 

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Sounds like you need to add a capacitor to your stereo set up and add an extra battery if you are going to add lights with your current set up. :beer:
 

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stock single battery and no capacitor is really running hard on your electrical system. Should have been done..
 

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A very common misconception is that the battery is the main resource for electrical power in a car. This is incorrect as the main source for vehicle power is the alternator. The battery is a RESERVE that is only used to crank the engine at start up and to provide power when the alternator is overwhelmed or off. If you're experiencing blinking headlights when your stereo hits bass notes then the problem is your alternator; you need a unit that provides more power.

A capacitor is similar to a battery in the sense that it stores electrical energy but it's different in the sense of how it releases that energy. A battery is designed to release electricity in a slow, constant manner whereas a capacitor is designed to release the electricity in a quick burst. This quick burst of electricity CAN be a plus when dealing with rapid, hard hitting bass notes but at the end of the day it's nothing more then a band aid. To correctly fix the issue you NEED to upgrade your alternator or you will eventually kill your battery.

Another common misconception is that a dual battery setup will help in scenarios like this which just isn't the case. The alternator is the main source of power so it doesn't matter if there is a single battery or two. If your alternator is not strong enough to handle all of your after market accessories along with a single battery it definitely can't handle all the accessories plus the chore of charging TWO batteries. A dual battery setup is only beneficial if you see yourself using excessive amounts of power while the vehicle is turned off because it isolates the main battery and prevents it from draining.

A dual battery setup is preferred if you like to play your high octane stereo while sitting around the campfire with the vehicle off otherwise the alternator is handling ALL of the electrical needs. This is why AEV has a feature in it's ProCal programmer that sets the RPMs at idle to a higher value. This higher RPM value gets the alternator spinning faster which in turn provides MORE power to the winch. The only way the vehicle's battery is used in this scenario is if the alternator can't handle the task.

In a nutshell, get a more powerful alternator. Good luck. :beer:
 

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A very common misconception is that the battery is the main resource for electrical power in a car. This is incorrect as the main source for vehicle power is the alternator. The battery is a RESERVE that is only used to crank the engine at start up and to provide power when the alternator is overwhelmed or off. If you're experiencing blinking headlights when your stereo hits bass notes then the problem is your alternator; you need a unit that provides more power.

A capacitor is similar to a battery in the sense that it stores electrical energy but it's different in the sense of how it releases that energy. A battery is designed to release electricity in a slow, constant manner whereas a capacitor is designed to release the electricity in a quick burst. This quick burst of electricity CAN be a plus when dealing with rapid, hard hitting bass notes but at the end of the day it's nothing more then a band aid. To correctly fix the issue you NEED to upgrade your alternator or you will eventually kill your battery.

Another common misconception is that a dual battery setup will help in scenarios like this which just isn't the case. The alternator is the main source of power so it doesn't matter if there is a single battery or two. If your alternator is not strong enough to handle all of your after market accessories along with a single battery it definitely can't handle all the accessories plus the chore of charging TWO batteries. A dual battery setup is only beneficial if you see yourself using excessive amounts of power while the vehicle is turned off because it isolates the main battery and prevents it from draining.

A dual battery setup is preferred if you like to play your high octane stereo while sitting around the campfire with the vehicle off otherwise the alternator is handling ALL of the electrical needs. This is why AEV has a feature in it's ProCal programmer that sets the RPMs at idle to a higher value. This higher RPM value gets the alternator spinning faster which in turn provides MORE power to the winch. The only way the vehicle's battery is used in this scenario is if the alternator can't handle the task.

In a nutshell, get a more powerful alternator. Good luck. :beer:
This :glasses:
 

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makes 200+ amps to power everything while the engine is running.
dual batteries will let you play longer with the Jeep off and still be able to start it when you want to leave.
Dual batteries main advantage is you isolate one battery for just running the Jeep, the other for accessories like stereo, winch, lights, etc.
Capacitors just help the very short peak current draws like when the bass hits- kind of like a buffer.



http://www.mean-green.com/store/proddetail.cfm?CFID=700097&CFTOKEN=64198086&ItemID=576&CategoryID=3

http://cgi.ebay.com/ebaymotors/07-1...rQ5fTruckQ5fPartsQ5fAccessories#ht_1056wt_939
 

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A very common misconception is that the battery is the main resource for electrical power in a car. This is incorrect as the main source for vehicle power is the alternator. The battery is a RESERVE that is only used to crank the engine at start up and to provide power when the alternator is overwhelmed or off. If you're experiencing blinking headlights when your stereo hits bass notes then the problem is your alternator; you need a unit that provides more power.
Battery capacity is what's needed for intermittent loads like a stereo.

If you're talking constant, sustained loads like running 100 amps worth of lighting for hours of night wheeling, then sure the alternator is what you want to upgrade.



Another common misconception is that a dual battery setup will help in scenarios like this which just isn't the case. The alternator is the main source of power so it doesn't matter if there is a single battery or two. If your alternator is not strong enough to handle all of your after market accessories along with a single battery it definitely can't handle all the accessories plus the chore of charging TWO batteries. A dual battery setup is only beneficial if you see yourself using excessive amounts of power while the vehicle is turned off because it isolates the main battery and prevents it from draining.
The alternator charges the batteries. The batteries power accessories. Alternators don't power accessories directly. The only time load is increased on the alternator is if the accessory load is large enough and sustained for long enough to drop the voltage on the batteries.


Very few loads are large AND sustained, requiring an upgraded alternator. Not winches, not (most) stereos, not air compressors, etc. In fact, the only electrical accessory I can think of that would benefit from an upgraded alternator would be running TONS of lighting while wheeling at night.
 

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I'll use extremes to illustrate.

If the alternator is the critical factor, then put a lawnmower battery in your Jeep with an upgraded alternator. It's not going to work.

If it's batteries, then put dual Odyssey PC1500s and a 65 amp alternator. You still be able to winch & bump your stereo just fine.
 

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I'll use extremes to illustrate.

If the alternator is the critical factor, then put a lawnmower battery in your Jeep with an upgraded alternator. It's not going to work.

If it's batteries, then put dual Odyssey PC1500s and a 65 amp alternator. You still be able to winch & bump your stereo just fine.
Your point that the battery and alternator exist in a symbiotic relationship is accurate. But if one implies that just by throwing in a higher capacity battery to compensate for lack of power then that's not an accurate statement. The solution starts at the alternator and can be aided by upgraded technology in the battery. In most cases, simply upgrading the alternator will fix the issue the original poster is experiencing.

So let's dissect what the original poster is experiencing. As his stereo hits bass notes his headlights dim. Why does this happen? It happens because as you pointed out the electrical system (alternator/battery) cannot keep up with the demand. Why can't it keep up with the demand? It's because the draw on the battery from the stereo exceeds the rate and ability of the alternator to match it. If the original poster upgrades the alternator the battery can stay charged and meet those electrical demands without the addition of an extra battery or capacitor.

If the above isn't the case then please correct me in layman's terms. :)

:beer:
 

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People always seem to overlook the obvious, do the simple stuff first.
-Stock ground is extremely weak; you definitely need to upgrade it.
-Upgrade the power cable from the battery to the alternator, same story stock wire is just weak.
-Use hi quality cable, a cheap 0 Gauge will give you more problem then some hi quality gage 4
-The alternator is powerful enough for the application 160 amp .....we only talking about 1000 rms max .
- Are we talking peak or rms power?
-Battery is a must, not just for the sound system but the vehicle in general, as the wire Chrysler did very cheap in that department.
-Adjust the gain properly on the amp, make sure the design of the box suits your speaker, A proper design might draw less power and give you better bass response I said might!


Dimming light is from bad grounding or cheap wire period, its always the first thing to look in these case.
 

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Here's a goofy way to look at it.....


It's really no different than a kid's money.

The size of your alternator is like the allowance.

The capacity of your batteries is similar to the size of your piggy bank. The piggy bank has a maximum amount of change it can hold. The batteries have a maximum amount of amp/hours it can store.

Your electrical accessories are your spending habits.

Some spending is large, but infrequent. Like winching, stereo bass hits, etc.

Some spending is consistent like lighting.

If the kid is spending money non-stop, then the piggy bank will eventually run out because the allowance can't keep up.

If the kids has a reasonable allowance and a big piggy bank, occasionally he can safely splurge on some big items.



My point is, that most electrical loads are intermittent. The alternator doesn't have to keep up with them real-time. The batteries have the capacity to supply 400 amps to the winch for a few minutes, and then has an hour to charge back up. The stereo may be hitting bass, but it's only a few notes.

Basically, if the sum continuous amp load of the accessories is higher than the alternator's max output, then sure, at some point your batteries will be discharged. A bigger alternator fixes that. But loads like that are really uncommon.
 

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Oh damn, how hard can this get??? He has a high out put stereo, his lights dim when the subs hit. So the fix for the sudden pulse is a capacitor. That WILL fix the light dimming problem. Yes dual batteries would make it safer, and a high output alternator would help charge the system. Any one that knows anything about High output stereos knows this. :beer: That's all and you guys can continue to argue!:thefinger::thefinger:
 

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Just figured I'd chime in quick. I've had a lot of Hugh end stereos and installed them. It's been said before but I've seen it 100s of times. Add mad amps and wonder what's wrong

If going big
Upgrade the stuff mentioned above
Ground and power wires to the alt.
Upgrade the alt.
Caps.
Good big enough wire
Battery

Keep in mind adding extra batteries actually adds more load on an alt. This isn't obvious on a normal system but an over taxed system with the stock alt you will kill the alternator quick
 

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Just figured I'd chime in quick. I've had a lot of Hugh end stereos and installed them. It's been said before but I've seen it 100s of times. Add mad amps and wonder what's wrong

If going big
Upgrade the stuff mentioned above
Ground and power wires to the alt.
Upgrade the alt.
Caps.
Good big enough wire
Battery

Keep in mind adding extra batteries actually adds more load on an alt. This isn't obvious on a normal system but an over taxed system with the stock alt you will kill the alternator quick
AHHH, no red star, but actually good info. Might want to listen to this guy!:thefinger::thefinger:
 

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Keep in mind adding extra batteries actually adds more load on an alt. This isn't obvious on a normal system but an over taxed system with the stock alt you will kill the alternator quick
Normally true, but not with the Smart Isolator in the Benchmark Stage 3 Kit. It charges 1 battery at a time to reduce load on the alternator.


To the OP, start with an inexpensive car stereo cap. That will probably help a lot. Then look into dual batteries or upgraded alternator. :smokin:
 

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Discussion Starter #19
All great info, Thank you everyone. I think I'll start with a capacitor and a stereo cap and see where that leaves me. Then if that doesnt help I'll be ordering a benchmark stage 3 kit...... Just throwing this out there, I'm going to buy HID bulbs for my headlights and since they draw less power do you think that the headlight dimming would decrease at all?
 

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All great info, Thank you everyone. I think I'll start with a capacitor and a stereo cap and see where that leaves me. Then if that doesnt help I'll be ordering a benchmark stage 3 kit...... Just throwing this out there, I'm going to buy HID bulbs for my headlights and since they draw less power do you think that the headlight dimming would decrease at all?
Going to HID bulbs will not help the problem with the lights dimming when your subs hit. Your system is needing constant power, and with the stock jeep set up, it can't keep up. Either turn the boom boom down, or follow the advice above:beer:
 
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