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2006 chevy trailblazer_ls
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A little help with some dimming lights

Just installed 1200 watt Hifonics amp with Hifonics 12" atlas. Lights do dim when the woofer hits. I though about running a secondary battery. Any opinions to lessen the dimming.
 

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Discussion Starter #24
Not to sound horibly new but what do you mean by BIG THREE?
Any elaboration?
The big 3 is upgrading (adding to) the factory wiring for the following:
Alternator to Battery Positive
Battery Negative to Chassis Ground
Chassis Ground to Engine Block

This should be done with a good 4 gauge wiring (you can go bigger, but unless you have a competition system then it would be overkill and not cost effective)
 

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Awsome sounds like an easy and necesary mod that i will be conducting, thanks for the imput. At what point do i need to consider getting a secondary battery for my amplifier?
 

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Discussion Starter #26
I know I'm late but I have this problem that is bugging me well I bought the Yellow top Duralast and hook up 4ch hifonics amp and 1 12" pioneer premier and the 4 power acoustik 6 1/2 on the door panels. So one day while I was finish cleaning my throttle body and when I was thightning my negative cable to the battery my socket wrench hit the middle cable on the delphi fuse panel in front of the battery and now my lights dimm everytime the bass kicks in. what can I do to fix this problem?. Any help is appreciated.
I guess I'm sorry catching up on this one... So I assume you didn't have any dimming problems previous to the accidental toughing of negative battery to the Aux. positive on the panel... Is that right?
If so you may have shorted out the wiring or even the battery itself enough to make either of them weaker... Do you know what voltage you were charging at before and what your battery sat at with the engine off? If you do you may want to check it again to see if there has been any loss. You may also want to check to make sure there is no burn residue on the connection of the aux. post on the panel.
 

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Discussion Starter #27
Awsome sounds like an easy and necesary mod that i will be conducting, thanks for the imput. At what point do i need to consider getting a secondary battery for my amplifier?
It is a required mod for anyone with any serious upgraded sound system.
As for a secondary battery you may want to look into it if you decide to go with an additional amp for the rest of your system (2 channel for front components or 4 channel for all the way around)... If you decide to go with something doubling up your power you currently have for subs (2000w rms and up or more) then you'll want to start thinking about upgrading your alternator to a high output unit to create more power.
 

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Adding a cap to a system will allow the amplifiers to run more efficiently. What it does is fill in the power gap for those short bursts like bass tones. I replaced my battery with a deep cycle and have a 2 farad cap. But I also have a high output alternator. You cant get power from nowhere , the alternator is the only thing that will add more power. The cap will keep the power more consistant to the amps and the deep cycle battery can take the abuse wile the car isnt running.
 

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2004 chevy trailblazer_ls
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I guess I'm sorry catching up on this one... So I assume you didn't have any dimming problems previous to the accidental toughing of negative battery to the Aux. positive on the panel... Is that right?
If so you may have shorted out the wiring or even the battery itself enough to make either of them weaker... Do you know what voltage you were charging at before and what your battery sat at with the engine off? If you do you may want to check it again to see if there has been any loss. You may also want to check to make sure there is no burn residue on the connection of the aux. post on the panel.
I don't know much about batteries but I do see some burn residue on the center post. There is a fuse that reads "Little Mega Fuse" may that be it since the burn post is hook up to it.I had Kragen check the battery and the altenator with some machine and it came out good. :thx for all the info this is driving be crazy when I drive at night my lights just dim to the beat I hate it.
 

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I wouldnt say batteries are better than a cap. You are not compairing apples to apples. They are both good for different things. And depending on your power needs it is best to have both. Starter batt and 2nd both deep cycle and a cap with .5 to 1 farad per 1000 watts.
 

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2003 chevy trailblazer_ls
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In my opinion, a capacitor is really NEVER an appropriate solution.

If your electrical system is unable to keep up with the demands of your draw, then -- logically -- a capacitor cannot help.

Everyone's argument in support of a capacitor always comes down to "quick" power. Where, allegedly, a battery cannot "keep up".

But a capacitor is only useful for a fraction of a second. Once drained, the capacitor becomes an additional load on the electrical system -- the same electrical system that these proponents "claim" couldn't support the amp, to begin with.


Adding more load is never the solution to a load problem... You need to address the supply, and that is battery/alternator/wiring.
 

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In my opinion, a capacitor is really NEVER an appropriate solution.

If your electrical system is unable to keep up with the demands of your draw, then -- logically -- a capacitor cannot help.
"Demands of draw" is not a constant, flat model. Music is dynamic and so is the power draw required to reproduce it.

Where a capacitor can help is with a peak or spike in draw that your battery and alternator cannot supply enough fast enough, but otherwise can handle supplying average draw enough and fast enough. How many people's situation fits into that band I don't know, but probably a lot less than are buying caps is my guess.

As you say, a cap will not help to provide power for average draw needs. HO alternator is what is needed and whatever else to go with it as appropriate.
 

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"Demands of draw" is not a constant, flat model. Music is dynamic and so is the power draw required to reproduce it.

Where a capacitor can help is with a peak or spike in draw that your battery and alternator cannot supply enough fast enough, but otherwise can handle supplying average draw enough and fast enough. How many people's situation fits into that band I don't know, but probably a lot less than are buying caps is my guess.

As you say, a cap will not help to provide power for average draw needs. HO alternator is what is needed and whatever else to go with it as appropriate.
The real truth!
I like dedicated grounds back to the battery rather than through the chassis as well. Mostly noticeable with video and/or earphones, in my experience. (40+ yrs)
 

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Alright lets get a little simplified,

Water is the best representation of electricity so I'll break it down as such

Battery=Big Bucket smaller valve to empty
Capacitor=Small Bucket Large valve to empty
Alternator=spigot on the house

The amp uses variable amounts of water to run based on the given load (music) this load is dynamic meaning it constantly changes. the spigot (to simplify things) produces a constant flow of water into the buckets. When the amp needs large amounts of water it will drain the cap quickly and then it takes time for the cap to refill. A cap is useful in the premise that music does not demand high current all the time. Thus the cap will drain on the big bass hit and recharge after, this is helpful because you are not normally listening to a test tone at max capacity. Therefore the cap will recharge when the load is not as great and help maintain a constant flow of water to the amp. However the cap requires just as much water to charge as it did to discharge this is why it will not help with dimming lights. The amplifier will run at a more constant input voltage but the current draw (requirement for water) is the same just offset from peak load (big bass hit). The battery is great for maintaining voltage at a constant load and helps provide current during and after peak loads.

The spigot (alternator) still needs to fill both of these buckets and if the buckets are emptying at a faster rate than the water flows from the spigot dimming and poor electrical performance will result. This is why an alternator that is capable of handling a higher flow (output current) is the the answer to dimming lights and poor electrical performance. Think of a regular alternator as a garden hose spigot and a high output alternator as a fire hydrant.

Another way to think of it is the cap is loaning the amp stored power for needs now and getting its power back when the amps needs are less. Both a battery and a capacitor have their place in a good electrical system but neither will do you any good if they are not fed by a proper alternator.

This post is not meant to talk down to anyone it is simply a easy way to represent what we are talking about.
 

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Everyone likes to argue discharge rate when the most important issue is recharge rate. Once a battery sees a substantial drain then it labors to catch back up to it's maximum potential. In most occasions you have to remove the demand. A capacitor on the other hand will recharge as quickly as it discharges. And like batteries, not all capacitors are created equal. A capacitor with a 12v surge (walmart, no name) will not match the performance that you get from a 16v-20v surge (Phoenix Gold, Rockfor Fosgate) unit. You cannot expect an item that surges below your vehicle output to provide any assistance when in itself creates a bottleneck. I have never had anyone complain or come back to me in the past after upgrading them to a capacitor and sufficient power wire.
 

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A very good explaination, IMO. It only highlights that a capacitor is just a bandaid for a weak power source.
You are correct but I would never use a cap to fix a poor power source. A cap isn't even a bandaid for a weak power source it is designed to enhance a strong power source.

Now lets get a little technical.

Lets assume a 1500w rms class d amp has an efficiency rating of 80% and that you charging system maintains a 13v output.

1500/13=115 amps at 100% efficiency
115/.80=143 amps at 80% efficiency

This means at the rms rating on the amp it will require 143 amps to produce 1500w at 13v input (i Know this excludes other factors but that would be a little too technical for the sake of this argument)

Now lets assume this same amp has a max power rating of 2500w. Which means it can produce this much power for a very short time(again realistically you will never see this amount of output but again for the sake of argument)

2500/13=192 amps at 100% efficiency
192/.80=240 amps at 80% efficiency

The difference in power requirement at 80% efficiency between rms and peak is 97 amps while you would want to put an alternator in that would handle the additional load it would still pull a huge draw on the charging system having a cap in place allows that additional 97 amps to be drawn from the system when the amp no longer needs that power therefore the amp won't "see" that system draw and will run closer to the 13v at all times. As stated many times a cap can't create extra power but it can store and release that power at the peak load situations then in turn recharge when the system load is relatively low thus spreading out or delaying the power need from the charging system.

On competition systems the reason that batteries are used instead of caps is they need to produce power long enough for the subs to produce max spl. A cap would not give a long enough burst of power to get a sufficient reading.
 
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