# Question about the charging system



## jstoner22 (Aug 21, 2012)

You shouldn't have any issues. The alternator is stout enough that with the proper wiring, it should handle your amp no problem.

This isn't a given though. What kind of draw does your amp have at the impedance you are going to be running at?

This is important because it can greatly change things. For example, my sub amp draws and average of 12amps @4ohm, 24amps @2ohm and 34amps @1ohm.
If putting out continuous power ratings, it will pull 44amps @4ohm.

As you can see, the amount of draw/strain on your alternator can greatly vary depending on application.


I'm also hoping you are going to continue that 1/0 into your main runs as well? Not just your big 3?


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## CanaryGT (Aug 12, 2013)

Are you just talking about taking the Watts and Dividing the voltage? If the vehicle runs 14.4 Volts and its a 1200watt RMS amp @ 2ohm then it would draw 83.3 Amps. At 12v thats 100 Amps. 

Input for the Amp will only accept 4 Gauge. I could in theory run a Distro block with 0 Gauge then Run off that, I already have the parts, but usually I feel that unless the Amp itself can take and thicker gauge wire it doesnt help.


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## 2013LT (Jul 3, 2013)

You will be okay. This depends on how the ELD reacts to amp addons. Does anyone know if the ELD compensates for the additional wattage of an amplifier or if it draws it from the battery?


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## Smurfenstein (Nov 16, 2011)

I'm running a 2300 and 475 amp in my car with the 1/0 gauge Big 3 kit and it takes two phones charging, and vol 30+ to make my headlights flicker on/off. And thats a problem with the battery, since my voltage meter never drops below 14v on the DIC read-out. With no phones charging I can have my engine off, and blast my stereo at vol 40 for ~20-30mins, as well as have LED cathodes that illuminate the subs left on with the music off for an hour or two and still start my car up without a hitch.


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## Themills (Sep 1, 2016)

Looking up a 1200 rms online a grabbed the specs off of a RockFosgate mono-block amp. Reading over the specs it has 4 awg max inputs for power and a 100a fuse. Back in the day Rockford was the amp you went to for subs. They cost a pretty penny however the quality of the product made them worth it. Then RF went mainstream and was in every big box store and mass producing product. Still decent product however the quality starting suffering.

Back to the specs the 1200 rms is at one ohm and is stable according to the box. Again back in the day a quality amp with those specs would be easily around a 1k not the 300 list price. However the 100 amp fuse means business so I will go that it might hit those numbers it claims however the 1.0% THD means it will be dirty in sound quality. A great quality amp is .05% or below. With all that being said entry level equipment allows people to enter in the world of aftermarket audio which 10x times better than stock even at entry.

Back to the 4awg input on the amplifier. If this is your only amp you ever plan on putting into the system then 4 awg power is all that is ever going to be needed. 1/0 kit is simply overkill. Now if you are planning on multi amp system in the future then absolutely run the bigger wire. People will say the big, the better however you can think of it like road construction on a 3 lane highway merging into the 2 lanes. No matter what you do there will be a reduction in flow when the opening is smaller than demand there will be a back up in the flow.

Now even if this old guy is talking crazy let's dive into the 100 amp fuse issue. If the amp is really drawing serious power then the 130 amp stock alternator is going to be seriously lacking. Lets use a modest 50 amp draw off the RF amp at normal volumes. Do honestly think there is 50 extra amps at all times in a stock alternator? Maybe during the day at normal to cold temps.

3rd point, most manufacturers will pad the numbers on product to increase sales. The old saying if it sounds to good to be true, then it isn't true. Maybe they did get the product to produce the numbers it claim in perfect conditions one time. Again with the example I'm using 1.0 THD doesn't require an expensive power block in the amp so it probably does what it says from Rockford.

I know this sounds like I'm hating on entry level product however nothing could be farther from the truth. With the cruze we purchased a couple weeks ago I'm looking to overhaul the sound system on a budget target of under 1k. Being an former employee of selling and installing there will be no labor cost for me so it's a fair target. If I was going to competition system that 1k would get me my rca's and power cabling.

A suggestion for any system that doesn't want to replace the alternator is adding at least 1 full farad capacitor with an upgraded battery. (Optima Gel Cell back in the day was my preferred battery). It gives quick bursts of energy for that hard hitting bass and is way cheaper for smaller systems that push the alternators.


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## NickD (Dec 10, 2011)

1,200 watts sounds cool, could build a large speaker on a utility trailer and mount 40 15" speakers on it.

30 watts is about all you can apply to a 15" speaker without getting distortion. 40 times 30 is 1,200.

Mounting four 15" speakers on a bell tower with 25 watts each gave a hearing range of four miles a full level, but really had to cut that down.

But just think what you could do with 40 such speakers.


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