Batteries - Which brand How many? Need Help!

[negolien]

I would NOT suggest running an amp like that on a single battery that's retarded advice just my opinion though /shrug.

 

[Dmac1991]

I heard more batteries equals less work for your alternater, so the more batteries you run, the longer your alternater should last. Of course, when you compare the price of batteries, to the price of alternaters, I don't think it will save you any money running a ton of batteries if you don't need them.

you're sadly mistaken

more batteries = more work from your alternator keeping all those batteries charged

in OP's case, 1 D3100 in the rear, and an AGM underhood would net him fine

 

[Dmac1991]

I would NOT suggest running an amp like that on a single battery that's retarded advice just my opinion though /shrug.

His alt would be the brunt of most of the work. One AGM underhood and a Group 31 in the back, he's gold

 

[LosIsATool 5,000+ posts]

You guys really dont understand power flows from the highest point? The highest point is the source, in this case its the alternator. That being said the amp as long as its not ran dirty will be powered by the alt and rarly touch the batteries.

 

[negolien]

LOL sure whatever you say bro...that's 2 batteries not one so yes I agree that would be best.

 

[LosIsATool 5,000+ posts]

LOL sure whatever you say bro...

I really have no idea.. Only had a 6000 watt daily driver that stayed above 14v. I guess the alt does nothing.

 

[Jeffdachef 5,000+ posts]

Just run the amp monitor voltages and upgrade as necessary.

 

[thirdgen]

you're sadly mistaken
more batteries = more work from your alternator keeping all those batteries charged

I didn't mean for it to be fact. It's just what someone told me, so I posted it to see. Now I know correct.

 

[n2audio 5,000+ posts]

You guys really dont understand power flows from the highest point? The highest point is the source, in this case its the alternator. That being said the amp as long as its not ran dirty will be powered by the alt and rarly touch the batteries.

LOL sure whatever you say bro...that's 2 batteries not one so yes I agree that would be best.

Neg -- Assuming you posess SOME ability to think for yourself, this shouldn't be that hard to understand...

The primary factor here is the 320A alt. That is a LOT of available current AT 14+ VOLTS.

Batteries -- while generally a helpful component -- will NOT even be involved with power delivery until the alternator is MAXED OUT and the system drops to

As was stated previously -- at idle, where the alt's output is surely much less than 320A, with the sound system at high volume and playing heavy bass the alt is likely to be maxed out and the battery/batteries would come into play.

Unless that's the way we're listening these days it can certainly be argued that one healthy battery is all that's needed for this set up to perform well.

 

[shizzzon 10+ year member]

So all the pissing aside...Your claim is we need 2nd batts and ~$100 of wiring in our 1000+w set ups to access float charge where virtually no current is available?

Let me jump right on that //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

This makes absolutely no sense

In his defence.. He is a salesman

No and not on here either. A Distributor.

I would NOT suggest running an amp like that on a single battery that's retarded advice just my opinion though /shrug.

You need to analyze the entire system, not just one component.

His alt would be the brunt of most of the work. One AGM underhood and a Group 31 in the back, he's gold

Exactly.

I really have no idea.. Only had a 6000 watt daily driver that stayed above 14v. I guess the alt does nothing.

Well, this will be interesting because this is where i can get technical.

Running 6kw on an alt still above 14v and about ~300a capable means the regulator wasn't even stressing at the load so lets say it was about 250A out.

That's about 3,600w @14.5v. Assume 80% efficiency based on the amplifier seeing a curve of around 2-3 ohms, that's 2,900w out.

Based on this analogy, you could run a single starting battery and something extremely small in the rear like a D1200 which is around 43ah.

My advise is typically based on people running their amplifiers at nominal impedance loads of 0.5ohms and yes my advise still stands on doing that in the OP's question based on the entire electrical system capability.

Neg -- Assuming you posess SOME ability to think for yourself, this shouldn't be that hard to understand...The primary factor here is the 320A alt. That is a LOT of available current AT 14+ VOLTS.

Batteries -- while generally a helpful component -- will NOT even be involved with power delivery until the alternator is MAXED OUT and the system drops to

As was stated previously -- at idle, where the alt's output is surely much less than 320A, with the sound system at high volume and playing heavy bass the alt is likely to be maxed out and the battery/batteries would come into play.

Unless that's the way we're listening these days it can certainly be argued that one healthy battery is all that's needed for this set up to perform well.

Don't try and convince yourself this is true.

Batteries are still used even if alternator appears to be fully capable based on voltage.

Assuming you have a voltmeter you are looking at, what is it's refresh rate? About twice a second?

Assuming that's what you have, if that's the ONLY evidence you are using to conclude your experience, then you are far from correct.

If you only want to use that as your evidence, one of our companies manufactures a module that monitors voltage changes at 5,000x a second.

Fastest car audio device ever produced.

But, i will explain why anyways-

Back a long time ago, there was a reason why stiffening capacitors were such "a thing".

They would handle quick spurts of high current to LEVEL the voltage.

We have much better regulators in alternators now and stiffening capacitors aren't necessary.

So let's fast forward to today.

Now we use batteries and Ultracapacitors.

Ultracapacitors are a BIG thing to use in industrial applications where powering up 1,000s of amps worth of motors are required.

UCs take that load off the batteries just fine.

Translate this into car audio where both batteries and UCs are now used.

When a rapid shift in current draw is required, the alternator cannot act quick enough to supply the initial rush.

That is where the battery or UC come into play.

On a slow cycle voltmeter, you won't see this. On a DMM, you won't see this.

Amplifiers don't care what you see, they care what it sees.

A user who's voltmeter is showing dipping down to 11.8v could be dipping over 1v lower than that on spikes if using proper tools to measure.

Point is batteries are still used as the ESR equivalent as well as the ESR equivalent rating of UCs are MUCH MUCH MUCH lower than the combined resistance of the alternator based on distance.

Alternator just provides the majority of sustained power because of the higher control of sustained voltage.

A tip- if you only used UCs for car audio with your alternator, the SoC voltage at the UC is the voltage at the alternator.

Something to think about, //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

However, i'm more proned to suggest LiFePO4 over UCs for those needing to run over $1k of agm batts, LiFePO4s should probably excel over agm and UCs as wel.

 

[n2audio 5,000+ posts]

Don't try and convince yourself this is true.

Batteries are still used even if alternator appears to be fully capable based on voltage.

Assuming you have a voltmeter you are looking at, what is it's refresh rate? About twice a second?

Assuming that's what you have, if that's the ONLY evidence you are using to conclude your experience, then you are far from correct.

If you only want to use that as your evidence, one of our companies manufactures a module that monitors voltage changes at 5,000x a second.

Fastest car audio device ever produced.

I don't need an instrument to know what's happening. 5khz refresh rate doesn't do us a bit of good since we can't discern beyond about 30hz anyway.

Alt lag time -- sure. I assume about anyone interested in this discussion is aware of and has a reasonable understanding of it.

And if we're assuming music as the signal and given an amp capable of ~4kw and ~300A alt output a standard 12v battery should have NO problem covering the gaps w/o drastic vdrop. If you're seeing ~11v then you probably have a defective battery.

I watched my local auto electric shop run their analyzer on my old contour -- 110A alt, stock battery, about 1400w rms. I put in Bass Mekanik and blasted it.

Voltage never dropped below 12.6, but more surprisingly, current draw was never much above 60A -- crest factor is the main reason we can run 1000-1500w rms with stock electrical for years w/o any major issues.

Which also supports the opinion that 3800/320 and a good battery would be adequate -- not to say a 2nd battery is a bad idea. With an alt that big it stands to reason a good 2nd battery would probably help a little.

Back a long time ago, there was a reason why stiffening capacitors were such "a thing".

yeah, they had a big profit margin and not that many consumers were willing to track down the info and figure out just how little they actually did.

We have much better regulators in alternators now and stiffening capacitors aren't necessary.

What most of us have are amps with adequate power supplies with all the capacitance that is needed to maintain acceptable input voltage.