do i need a high powered alt.

Hi what I'm doing to my 78 Nova is I'm gonna use a 5 channel amp and add one CIG charger and a set of hid headlights and a KICKER ZX700.5 (11-ZX700.5) amp. do you think high powered amp is necessary or the stock 63 amp should do

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

Only if the existing alternator voltage is insufficient during normal use.

True I known newer cars can handle 10% more than needed but this is such an old car so long story short I'm going to need a high output

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

still_walkin wrote:

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newer cars can handle 10% more than needed

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Question #1 - where is that info from?

I read it on a forum on this site I'm guessing your saying its incorrect

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

From my experience you can get away with up to 500w with a analog amp,that is driving a subwoofer, with the stock alt. if you are using a 1 farad cap to spread the amps load out. If you're usung a digital amp which are much more effecient you can use a highe wattage amp. But like oldspark said total draw while in use is the determining factor based on voltage under load. If you can't turn on and use what you would normally use and maintain at least 12.5v full load then bigger alt will be needed as a reference.

True however capacitor is to store power when you need it .but have can I store it if I didn't have to spare in the first place. Me personally I would do the Ho alternator and big 3 but I trying to keep the car original as possible and the big 3 under the hood is gonna be noticeable. But a high output factory bolt on won't be noticeable

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

oldspark wrote:

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Only if the existing alternator voltage is insufficient during normal use.

---

Once again follow above. If you're running a sub you will need a cap with whatever alt you choose to use as the are not designed to take large spikes. And caps are designed to store voltage yes, but for the purpose of smoothing spikes which kills alternators. A large amount of people don't and replace alts because of it. See it all the time. As long as you can matian 12.5 volts or above with normal use for you then it won't be a problem.

Understand what your saying here's another scenarioin my other car I was using 3 digital amps and no cap one high output and a red top w/ the big3 and the voltage stayed above 12.5 and the salt has been running fine going on 4 years . But this is a more esessive example that caps are not as good as they seem. I decided I just going to upgrade the charging system and get a high output but hide the big 3

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

Key word "DIGITAL" which means less power draw per watt. The Amp you listed is a Class AB not D = digital. And Red Top Battery by design is simular to a cap and battery in design due to it's low internal resistence, unlike a standard battery. So to a point you can use a Red Top and no Cap.

Their you go so I'm saying you can design a system and not use a cap and a hi output can power the system without a cap;)

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

You didn't say you were going to use a Red Top battery! And a Cap is cheaper than replacing a good battery. If look is more important then cost then yes. Logically a Cap is the first step in upgrades of a system. Then alt and battery to alt wire. Then an aditional battery. FYI no audio pro would ever put together a system with out a Cap, even with all digital amps and Red Top batteries.

Now we are going off topic who doesn't add a bunch of electronic upgrades and not put a good battery under the hood. Look at all these cool things I have but it doesn't start. The very first thing you do when u start modifying the car with abunch of electronics is to beef up your charging system. The purpose of this thread in question could I get away without beefing it up and based on the amp I picked I cant so time to put in the zero gauge;)

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

still_walkin wrote:

---

Now we are going off topic who doesn't add a bunch of electronic upgrades and not put a good battery under the hood. Look at all these cool things I have but it doesn't start. The very first thing you do when u start modifying the car with abunch of electronics is to beef up your charging system. The purpose of this thread in question could I get away without beefing it up and based on the amp I picked I cant so time to put in the zero gauge;)

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Most DIYers don't and only you know how you will use the system which will determine the load on the system, do you listen to it loud with lots of BASS regular then yes upgrade is recomended, listen not so loud with no sub(s) upgrade probally not needed. If your combined amp's of draw dosen't exceed the output of the alt and voltage is above 12.5v to keep the battery from being discharged, then upgrade proably not needed. You can guess all that you want but until you install it and see it just a educated guess. As for the Big 3 for 1 Amp is not needed. If you do the Alt upgrade then alt to battery feed (4 ga)is recomended. Muliple amps (sub) then all three.

Sorry guys, I just returned.
I intended to replace my reply asking about the "10% extra" with a more direct reply...

The 10% means an upgrade may not be required.
VIZ - that 10% overhead is for a vehicle idling in peak-hour traffic in the cold dark rain. Hence the alternator outputs sufficiently - plus 10% reserve - at near idle speeds with headlights on, wipers on slow, heater fan and rear demister on, and normal audio, stop lights and indicators. And it will still recharge the battery after several short stops and longer than usual cranking times on an old battery.

Ergo, headlights & wipers & demister off and you have an extra 30A available.
Increase from idle speed and you have even more available.

Assume the 700W RMS amp is at 1/4 volume hence maybe 500W input. That's under 50A which the system may well handle.


My point is that I often see those types of "10% extra" or "minimum additional cost" statements. But 10% extra to what? [And if they theoretically needed a 67A alternator, they wouldn't build it, they'd get the next existing size (maybe 75A) or maybe a 90A or 120A alternator if they are cheaper (thru mass production, or with fitting and bracket costs etc).]    
As I see it, manufacturer's do not want vehicles to fail in the rainy dark cold peak-hour scenario I mentioned, so that is their baseline - NOT the "normal" daily cruise scenario.


How best to design? Well apart from being prepared to add the extra amp/load requirement (at 100% power all the time, or 25% half the time, etc?), it's by observation.
IOW a voltmeter. And preferably before the addition so you get familiar with how often the alternator is under-voltage yet the battery reliably cranks next time, or the battery is fully charged by the journey's end.
(Refer elsewhere to 12.7V and under being battery discharge, up to 14.4V being a normal charge, and over 14.4V long-term leading to battery destruction.)

Some have upgraded from 45A alternators to 200A alternators only to be worse off. (IE - many OEM alternators output more current at lowish RPM than do high-output alternators.)
And they only found out when their vehicle failed to crank later...
Now, if they had a voltmeter...!


As to later posts, forget caps. They do nothing to increase the power output of alternators - they can only store charge. And that charge is far exceeded by a battery. (Even a 1.2AH battery holds more charge than a BIG multi-Farad capacitor.)

In general, the only use for a cap is in BIG audio systems (2-3kW and above) where adjacent AGM batteries are used, and that's ONLY to protect the AGM battery (ie, take off some of its surge requirements).
When caps are used for filtering, a battery is generally far superior, plus the battery has the advantage of a much larger capacity for better sag ride-thru.
If the extra battery (instead of the cap) is 7AH or 15AH or larger, it can be an emergency cranker. How many caps can do that?

Of course a 2nd battery must have some form of isolation when not in use. That might be an automated system (alternator controlled relay aka "the UIBI", or a voltage sensing or "smart" isolator), or even an IGN or switch controlled relay, or mechanical links.
Only when that is not practical or possible might a cap be considered - eg, a cap across headlights to minimise dips - but then a faulty cap will act the same as a faulty parallel battery.


As to caps or batteries and alternator loading, forget it.
Some say they reduce alternator loading though probably most say they increase alternator loading.
In fact the former is the truest (extra or bigger caps & batteries REDUCE the demands on the alternator), but it should be irrelevant anyhow since alternators are self-limiting wrt to output current, and only poor designs will fail under normal situations (including jump starts!).

If audio buffs reckon they increase loading, then they should logically support having smaller batteries, and of course never an AGM!
Of course they might only argue against a cap since they have no charge-current limit per se whereas batteries will have a limit (even if it exceeds their specification).
But audio buffs that are in to (peak) SPL competitions will usually tell you NOT to have a cap, and similarly not to use AGMs, or not electrically adjacent AGMs).


The other advantage of the voltmeter - your super-duper alternator has worn brushes and is dropping output. You'll know about it before it's too late. (It will also pre-alert you to a failing battery.)


There are lots of other considerations like do you need peak voltage (14.2-14.4V) or how often do you want the battery to discharge and recharge - and to what level.
I have only skimmed some basics.

Oh - and BTW - the BIG-3!

I listen to my music balanced the bass his and mids all balanced. As for the 4 gauge upgrade that was a no brainer that is what I ment by beefing up the charging system. But numbers are numbers and for me to blindly ignore specs install something that's gonna give me problems later on nope . I rather do it right the first time and move on to the next project. Thanks for your help I figured out how I'm gonna do this install .as for olds spark you hit it right on the button caps vs hi out puts. I WL be running the amp when the car is on or in acc but I saw some direct bolt alts online but I'm going to visit my local guy that does all my alts and see what he can do for me .

-------------
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

So oldspark what's your decision would you go with a smaller amp because the factory front is 4x10 and rear is 5x7 and a free air sub for the back I'm not looking for booming just basic sound

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

Yeah, it sounds like you're on the button.
As to caps, I think you know this site's arguments - as well as Richard Clark's views. (It amuses me when someone can't kill the falsity they started. Yes, that's a personal experience too LOL!)

As to AGMs, I'll avoid Optima discussions (just seach).

But my usual argument is if only using a single battery in the engine bay, then stick the original type - ie, flooded if it's a wet/flooded type.


As to swapping to an AGM for audio reasons and hence often destroying the main/cranking battery quicker whilst gaining little for the audio, if people thins it's worth that to gain a few milli-Ohms when the distribution to the amps is of similar or higher resistance...
We solve that with the Big-3 instead.
Only then we might consider an AGM if needed, but that would almost certainly be a "remote" AGM, ie adjacent to the amp. And that's usually a second battery so that we have cranking independence. (The longer starter-motor cable run means cranking is less damaging to the engine-bay mounted AGM.)

As to caps being cheaper. I have yet to see a multi-Farad cap that is cheaper than a 1.2AH 12V AGM battery. Again, not that that matters because of the cap's inferiority (read: uselessness in comparison to a battery for most situations).
Incidentally, do they have those pocket sized emergency starting batteries over there? Usually nothing more than a 1.2AH or ~2AH 12V AGM except for their inline charger.


And as I've posted, stick to an S-type alternator (ie, 2 wire).
Apart from charging based on the actual battery voltage as well as being able to easily increase the charging voltage if needed (eg, using diodes), you can base the charging voltage on the remote battery if desired - and then "chop" the output to the front battery if needed. Oops - I have yet again destroyed the livelihood of a few local self-interests.


If you try with your existing alternator before changing over, keep in mind that only a few minutes at reasonable RPM is enough to adequately recharge most batteries sufficiently (assuming the normal "no more than 20% discharge" for a cranking battery).
So hence maybe a final run with low amp volume if the system has been below its normal voltage - ie, normal being above 13.8V and usually ~14.2V.
If it is (say) 14.0 to 14.4V, it is charging the battery at its required rate.

Well to jump start a vehicle with the newer gm alternators while running greatly increases the likely hood that the regulator or rectifier in the alt will get damaged. As they don't like spikes and all new or remanufactured specificly say to fully charge the battery before installing the replacement or regulator damage will occur. I had to replace 2 of them so far one because she let the vehilce set for a couple of months and the jumped in and started it and a few minutes later the light charge light came on. The other jump started someone and the charge light came on a few miles later on his way home both vehicles had under or around 60,000 original miles when this occured. In both cases the rectifier was shot, replaced the rectifier and alt's tested good and have been running ever since. And standing voltage on flooded lead acid batteries is around 12.5 volts, and 12.7 for optima AGM here in the US. And the 12.7 was right from Optima tech support dept.

This was over 2 years ago and they haven't had a problem since so everyones opinion is subjective to their experiences. I have ran a Directed 1100D ISACA Certified Edition (4 ga direct to amp terminal, 1100wats @ 1 ohm, pulls up to 90 Amps)on a stock 105 amp cs-130 alt with a Diehard battery and a 1 farad cap for 5 years now and the alt and battery are still going strong. So take it anyway you like but there is more than 1 way to do things, oh and none of the Big 3 were done either. Thought about up grading the alt wire to battery but haven't done it yet.
Optima batteries here are $180 and up in the US, 1-Farad caps are $100 for a monitor top less for a non-monitor. Thats for brand name Caps there are cheaper ones than that from off brand companies.

Geez I keep missing these replies...

Still_walkin - I'm no amp nor speaker expert so that's a question for others. But IMO a bigger amp might be better provided it can still output well at lower volumes, and provided it isn't up high enough to blow the speakers. But gain adjustments should solve both issues.
And if it's too big for the alternator, turn it down until you get a copious alternator. (Overnight charging is an option, but that means the battery is being overly labored etc.)

Lurch - you have supported my argument(s) well.
Jumping etc won't blow regulators (that would be a really crap design!).
And what I consider poorly designed alternators can blow after starting on flat batteries. I had such experiences with Bosch alternators before returning to my typical albeit newer Jap alternators. It sounds like the GMs (Delphi?) are like Bosch. You have my commiserations.
My Bosch experience made me realise that the spouse's tale about keeping the jumper battery connected for a while after starting was not in fact a bullsh myth. (I was almost made an honorary Myth Busters member LOL!)
But that is due to underrated main diodes which IMO is pathetic. Surely one should be able to roll start a vehicle without blowing the alternator? After all, if the windings and current output is self-limiting....

But the above aren't spikes - they are longer overloads. Only lightning are some welding spikes should be able to kill alternator diodes - and that's from reverse biasing (above their PIV rating).


As to the Optima tech guys, I suggest they get some proper battery literature and read their own sales brochures.
12V lead-acid Batteries are ~12.7V fully charged (12.67V @ 25°C) though Optima often claim higher for their batteries, as well as a charging voltage higher than the normal maximum of 14.4V.

Thanks too for the pricing. 1.2AH batteries here are ~$15 and 7AH are ~$25-$30. Despite your cheaper prices, the battery still wins.

If you can show me the different behavior with and without the cap connected in your system I'd be obliged.
Mind you, I'd usually compare that to a system with a much cheaper 1.2AH or larger battery in the cap's place. You seem to be running a single battery so a cap is more likely to have a beneficial effect as opposed to common audio boot/trunk battery set-ups, but the cap is still not as good as a battery in lieu.   


I feel it's a pity you didn't upgrade the big 3 - that is an area where manufactures can minimise costs, and it could have saved you the cost of the cap.   
To increase vehicle electrical loads without increasing ground cable ratings is also risking expensive damage to the loads and vehicle.
But maybe the voltage across your amp at 90A is not significantly different to the front battery's voltage.

With out the cap the voltage would drop so low when a extreme bass note would hit at high volume, stopped at a light that the car would stop, and some times it would stutter. The cap stopped that and drasticly reduced the dimming ot the head lights. But that is the daily driver.

The othe car has the real stereo, Alpine CD player, 6 disc changer, Digital EQ, 2 x MRV-1000 (600w RMS each) Sub amps to 2 Cerwin Vega Stroker 12" subs, MRV-F400S (100w RMSx4) actual test sheet with AMP 165w x 4 @ 12.7 volts @4ohm CS-130 alt w/ice berg kit 200 amp stator, over drive 48mm pulley putting out 185 amps @ idle, 1-Farad Cap, 2 Optima Red Top batteries(800cca) front and Back connected by 1/0 gauge streetwires comp series power wire.

But you spent so much to stop that drop when a mere $15 would have done so much better. That's my point. Do a calc on how long that cap supplies current/voltage, or compare the Farad(s) you cap has to that of a battery.
Of course it's not surprising that the amp voltage dropped without having done the big-3. Whether that would have solved or worsened headlight dimming depends on its wiring.


It always gets me how amps that have an internal SMPS supply quote an output at a certain input voltage.
What gets me even more is high-power amps whose output power is proportional to the input voltage (squared) - it's as if the amps are a purely resistive load! (I have a Kicker PCB which I've been meaning to decipher wrt to its SMPS circuit to see why it/they should behave that way, but that's another day project...)


Is your other set-up's cap to protect the red-top, or to prevent dips?
If dips, how bad are the dips without the cap?

The amps are analog V12 series DC to DC direct. So even with the optimas wired in series ie no isolation with a 300 anl fuse front and back with the 1/0 wire and the over built alt the lights and voltage will still dip without the Cap a couple of volts with the system turn up to stupid loud. The amps are fused internally with 2 x 20 4-channel, and 2 x 30 sub amp each. The voltage drop is almost gone and the lights barely dim with the 1-Farad Cap. So I got another Matching 1-Farad Cap but never got around to installing it yet. It not the overall draw causing the problem it's the surge when the bass kicks in the dip,spike causes the problem at idle even with the overdrive pully to spin the allt faster which is usually required for big amp alts.

I must be missing something....

Your batteries are surely not in series. [I presume you mean they are parallel but directly connected without an isolator. (Good luck when one of them fails.)]

And "overall draw" - I presume you mean average etc? [Since the burb surge current draw is what is causing the dips.]

Is the 2nd battery next to the amps, or electrically remote (ie, with +ve and -ve connection to the amp exceeding a few milli-Ohms)?
Or conversely, when the 2nd battery is substituted for the cap - ie, same mounting terminals - how do the dips compare?


As to the overdrive pulley, many don't have that luxury due to their high revving of engines and alternator physical RPM limitations.
But that too supports my previous comment where many were worse off with hi-output alternators. (IE - they failed to consider their driving profile and alternator output curves.)    


still_walkin - I hope this isn't hijacking, but at the moment I see as more proof of the pie.

No its fine its good to got to the middle someone's issue they Dont know they have besides I'm seeing how others wire their stuff up and learning more as well shoot for it

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

oldspark wrote:

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I must be missing something....

Your batteries are surely not in series. [I presume you mean they are parallel but directly connected without an isolator. (Good luck when one of them fails.)]

And "overall draw" - I presume you mean average etc? [Since the burb surge current draw is what is causing the dips.]

Is the 2nd battery next to the amps, or electrically remote (ie, with +ve and -ve connection to the amp exceeding a few milli-Ohms)?
Or conversely, when the 2nd battery is substituted for the cap - ie, same mounting terminals - how do the dips compare?


As to the overdrive pulley, many don't have that luxury due to their high revving of engines and alternator physical RPM limitations.
But that too supports my previous comment where many were worse off with hi-output alternators. (IE - they failed to consider their driving profile and alternator output curves.)    


still_walkin - I hope this isn't hijacking, but at the moment I see as more proof of the pie.

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Sorry I mis-spoke I meant parallel direct (+,+),(-,-) and yes the 2nd battery is next to the amps with the cap between the 2nd battery and amps ie + from battery to + on Cap to Amp distrubution block and the same for - connection with 1/0 guage ground from battry to chassis.
When one of the fails? Just replaced both of them as they were 12 years old and weren't holding a charge any more with 2 more optima's.

Had it wired direct from 2nd battery to Amps to begin with thats why I added the Cap.

I always overdrive High-out put alts to boost the low rpm output because I have been doing this for awhile. The Ice berg kit for increased cooling of the alt with a hybrid ceramic ball bearing in the rear, to lengthen the bearing life span, as standard bearings don't handle the higher speed for that long in a 10x26x8. I have the alt built to the extreme limit of the cs-130 design it can handle with the Iceberg rear housing cooling kit.

You did well to get 12 years from an Optima. Let alone TWO in permanent parallel.

You also replaced both which is essential an any permanent-parallel (or any series) configuration. (The number I see where "only the faulty" battery in a series string or permanent-parallel battery bank is staggering.)


I'm still unsure why you added the cap, but its location leaves the voltage-sag issue unresolved. But I'll ditch that issue. I was surprised that another recent cap thread didn't get certain comments, but maybe others are tired of certain old issues.   


Thanks for the info.

I agree I'm. Unsure as well in my experience with the red top I haven't had any issues at all let alone charging or keeping voltage up. My system has changed from being too many amps to reasonable and a red top has never failed me

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1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

Yeah, normally I read how other batteries are better than Optimas, and cheaper (viz Kinetic, and more recently Deka stateside (long recommended here in Oz)).

But it seems many chose the yellow tops when probably they shouldn't. IE - they should be using reds.

And it's not uncommon that I read of long-life Optimas - though I recall only one 13-year old Optima and others reckoned that made it likely to get a free Optima replacement (LOL?) - and Lurch's were in parallel - ie, halving their reliability.
But I certainly read more about Optima fails than anything else.
And I note a trend where even those that have had certain "typical" Optima fails still swear by them (yet don't have other relevant battery experience).


However, maybe the 13 year old and Lurch's Optimas are from the time when Optima was good, before their alleged demise into recycled or non-pure lead or copper or whatever increased their failure rate.

Lurch's new red-tops will be interesting to life-cycle. Let's see - two times 3 months in parallel, that means both fail in 6 weeks LOL. (In that failure mode, 3 months would be valid.) But that 3 months was for yellows anyway.   (PS - NOTE that that's not an MTBF figure, it's merely a common fail time that I often read for yellows, and I cannot vouch for how good their charging systems or applications were - ie, it could well be a use fault.)


Again, a voltmeter (across the battery terminals) is the best option. It'll warn of under & over alternator voltage, and low battery state.


FYI - Optima for red-tops at 25°C (77°F) claim:-
12.8V OC fully charged (allow for surface charge depletion!).   
13.0 to 15.0V alternator charging (yet 13.2V...) & 13.2V to 13.8V float.
15.6V with unlimited charge current PROVIDED the battery remains under 51°C (125°F) (IOW not for engine bays; I assume a 10A charging limit above 51°C.)
And they are crankers, not deep-cycle.

As for mine I had it for 3 years and the reason I chose red or over yellow is I rather have better cranking that faster charging .keep in mind the car is a Cadillac and those things are all electronic so its juice hungry.

-------------
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"

Interesting statements considering the yellow has similar internal resistance and therefore should crank the same. (I'm looking at a yellow .0025mR spec versus the .003mR for the red, but they may be different capacities).
And the yellow may have higher terminal voltages (for reasons unknown).
But their internal resistances are for fully charged batteries (of course!) and can't be used for real recharge current data. (Internal resistance increases with increasing discharge level. Just as well, otherwise many flat batteries would explode (not really...) or wreck far more alternators!)

And charging limits are the same, ie, 10A unless under ~50C when no current limit applies.

But crankers are different to deep cycle by merit of construction - ie, for the same size (capacity?), high-current crankers have more thinner plates and hence more "current area" whereas deep-cycles have fewer but thicker plates to handle the greater discharge depth without as much plate damage.
And other batteries fall somewhere between the two high-current and high discharge-depth constructions.

And of course a big enough deep-cycle can supply adequate cranking capacity without significant damage. Conversely a big enough cranker can deliver a smaller deep-cycle's long discharge AH capacity (but still remaining within low %age cranker discharge depth limits).

Though the above is almost common-sense (once you realise it), I am often surprised at some battery discussions. People may discuss the same battery but with its 2 different specs for differing applications. One simple case involved an argument between a 7AH C-20 and a 4.2AH C-1 rated battery for the same application, yet they were the SAME battery!
I thought audio forums took the prize, but others are well in the running too - like the authoritative or respected dude that was pooing the efficiency of using a battery by testing what it took to replace the same charge it delivered - but at 12.7V! (IE - he recharged at 12.7V since that's what the battery was. Do not pass Go. Don not collect any money.)
And they are often full of the same "must match batteries when in parallel" for systems that have auto-isolators (ie, only paralleled when charging or required).

But some audio forums probably take the lead all things considered. By that I mean combining all their snippets into the overall system.   
Some readers may have read threads hereon by someone also on a certain south-east stateside audio forum. There were statements like housing batteries in the engine compartment for greater capacity due to the increase temperature (they must have at least started with lots of money...).
There was also a rule like 100AH per kW of audio. I could only find the first post with that statement, but never found its source or what it's based on. I suspect it's someone's version of the oft used 100A per kW (for 12V systems).
I suspect too that a certain "Farads per Amp" rule is likewise a twisted application of another general power rule of 5-10uF per Amp or 10,000uF per Amp depending on how you engineer it. I'm waiting for the day that someone quotes a source or basis, and thereby probably declare that all this cap stuff it for a certain voltage dip after a mere 10mSecs. Whilst I know that that short time may have some possible validity compared to batteries, I suspect most others will not know that connection. (Sorry for the double may & possible, but the latter may have validity wrt to one "theoretical" aspect of battery behavior, but I suspect it ignores another practical and real aspect.)
However that short time blows away any arguments for caps with burps lasting more than a fraction of a second, and then the battery continues and wins hands down (yes, even a $15 1.2AH).
Despite the above "general" rule I mentioned for 10,000uF aka 10mF per Amp, I know that some "quality" amps have 1mF per Watt of output, but that's a SMPS level - not the raw DC input level. (But that's where to add extra capacitance - NOT at the DC input level!! Not that money spenders are told that, or provided that option (though I understand why).)

Some know my views on how big amp design is totally flawed anyhow. IMO it's so stupid having the PSU in the rear-mounted amp instead of placing the PSU near the alternator and main battery and thereby distributing at least a ten-fold decrease in current to the amp(s) depending on local Regulations and their interpretation.
But there is so much money still to be spent on the current architecture (good pun eh?) that it may be a while before the split occurs. Of course multi-battery audio installations probably prefer the current method, and the long proposed conversion to 42V vehicle systems make the split system less attractive.

Geez, I kinda digressed, Again.   

Did I mention the local SPL competition I attended? (No - only about disconnecting caps for higher peak SPLs?).
I noted that all the vehicles except for one used wet audio-battery banks. And no - the AGM did not win.
And I barely noted any caps. Mind you even the AGM vehicle had more than enough AGMs to not require that (for AGM potection; there were about 10 or more AGMs).
I've been meaning to go back to the store that hosted the event and discuss the issue. Maybe one day... Maybe one day I'll also mount my single speaker and beat the lot of them LOL! But why add to my already jeopardised status?
But my point is that maybe the locals agree that caps decrease the peak SPL. That may also account for their use of wet cells.


Anyhow this reply started with aspects of Optima battery ratings. I guess the recent posts have resurfaced some old discussions.

BTW - that "SE-audio" member recently reappeared to discuss capacitors. I suspect he had some new found formal education that spurred him. Unfortunately he lost sight of - or failed to understand - some simple basics about when capacitors charge etc. It wasn't long before he got into formulae etc which were at that stage far from relevant. In some ways that reflects some common forum discussions - too little knowledge, or too new and specific detailed knowledge that has yet to mature.
[When I consider what I've just written, I realise the multitude of experience albeit "electrical" whether it be batteries, or the tiny (if any) capacitance required for high-frequency power conversion (ie, SMPS). Some of us know that an inductor complements a capacitor, yet rarely is inductance discussed. (Ah - that might be the next revolution - high inductance oxygen free cable!).]


And FYI - a great source for battery info that I oft recommend is Bill Darden's batteryfaq.org.
It's usually revised every few months (albethey minor - the basics don't change much), and now the downloadable Battery.Zip is listed on the home page rather than its old buried location in chapter 19.
I can't recall if Bill goes much into some of the AGM-dislikes that I have mentioned though I suspect it's readable between the lines as so much of battery detail is (ie, once you understand it, you realise something is covered in his writing), but he certainly did IMO palm-off aspects of paralleled batteries to elsewhere (clever Bill!!), though IMO that too is contained in his writings.

Maybe you suffered all the above for that link. Or did you just jump to it LOL?

And BTW again, great that your red top has lasted. It should last several more years.
I remember when I considered 3 years a good life for my wet batteries. But with better battery technology, and my move to improved vehicle electricals (especially the relatively recent conversion to all-in-one alternator-regulators, and maybe too the in-dash digital voltmeter), I now expect at least six years even with my abusive behavior.

"oldspark"

Since you believe so strongly in what you say and have learned over the years.
How about you opinion of Hybrid Battery Chargers and the like?

I follow you on most of your beliefs, but differ on a few or have had positive experiences with what I have used and how I used it, maintained it and the like.

I don't know everything just what I've learnd over the years based on need to do it myself and not pay some one to do it for me. My knowledge may be limited to specifics that I needed to learn, but I try and continue to learn along the way. I could never be an expert in any one area as I am to diverse in any thing that I can do myself, with research and planning I get what ever I set my mind to done.

I'm not sure what type of hybrids you mean.
If it's domestic cell hybrids, they aren't lead acid.
Hybrid technology still follows battery basics.
Hybrid cars ditto whether lead acid or lithium etc, or thru regenerative braking. And hybrid cars should not need ancillary charging - except for long idle periods
I don't think I'd have anything to add to what others say, just on what I'd sense as obviously wrong or inconsistent, or overkill or expensive or under spec, etc.
Not that I believe strongly in the above nor my previous posts. It's merely that I believe them to be correct, and then write to help others, or prevent waste, or promote understanding (including my own!). And my statements may have differing degrees of correctness about them. Besides, learnings do evolve.   


My knowledge too is largely what I needed to learn education and career wise, but there is a lot of ancillary stuff too whether thru hobbies or just plain luck meeting the right sources in areas of non-interest.

I know what has worked for you, but I'm trying to quantify that wrt to something tangible, or compare it to cheaper options with seemingly superior results.
I have been driving since Easter with no rear brakes instead relying on only the two fronts (which have the same shoe/lining sizes and drum diameters as the rears) and that has worked fine for me. Whether I'd claim or suggest it is as good or better than having all 4 brakes - let alone recommend it - is a different matter. And not that I would dare suggest such an illegal and unsafe installation, but still, it has worked fine for me. And that includes 1,000km destinations with treacherously steep descents, and I'm not known for being slow on rough roads, as well at typical peak hour and school traffic. Maybe I could ask why people are so keen on brake boosters or disk brakes, but I know the obvious and responsible response I'd get.


It's fine sticking to what works for you, however I'm curious where your beliefs differ.

I not advocating doing anything that can be dangerous. I paralleled the batterys but not with out proper fuse protection at both ends, proper ground, battery tray, alt. upgrade to handle charging 2 batteries and the such.

I was asking about Hybrid battery chargers, not batteries. Like the Schumacher Hybrid battery chargers, like the SC-10030A SPEED CHARGE AMP HYBRID BATTERY CHARGER & TESTER that I have.

I have done construction from foundations, and concrete to roofs and everything in between. HVAC, automobile repair engine rebuilds. PC builds Repair, network setup and repair. OS repair (WINDOWS) virus removal Bios Modifing, minor electronics repair. AKA Jack of all trades master of none.

They call that "hybrid"! Down here we'd call then walkers. **
Hybrid chargers generally refer to those for hybrid vehicles though they could also refer to domestic "multi-battery type" chargers, and before then the good old "hybrid technology" markobabble.     

I don't recall much about the Schumachers, just be wary of the Optima 10A limit (and since good battery chargers have battery temp sensing - don't they?).
And check if it has a memory to return to whatever state after a power fail.
I use a similar but smaller (4A) 6V/12V pulse-charger that was $25 from Aldi. That's cheaper here than the old-tech voltage chargers, and less than 1/3rd the price of the cheapest equivalent "smart" charger. It doesn't have a memory, but I don't care at that price. It's just nice being able to forget about leaving a charger connected, as well as its other advantages.


You are aware that paralleled AGM batteries can be dangerous? Read up on AGM thermal runaway.

Also permanent parallel connection compromises battery life. In simple terms, the reliabilty with respect to self failure is halved for 2 batteries.
If one collapses, it will cause the other(s) to collapse. That's annoying enough with wet cells, but AGMs have their added hazard.
An whilst not so bad for 2 parallels, ie, if one fails you only replace 2, but for 3 it means replacing all 3 (& three times as often), etc.
In simple reliability terms (eg, using MTTF or MTBF type data), it means buying 4 batteries for 2 in parallel, 9 for 3 in parallel, 16 for 4, etc in the same time it would normally take a single battery to fail. [I hope I got that right. I once wrote so many paraphrased explanations and got so bored, and now I'm regurging my ancient wording without thinking. And it is exacting and it's easy to get confused.)      


It sounds like we have similar backgrounds though negligible construction work for me, and a wasted some time picking up a qualification along the way.
I'm definitely DIY, jack of many but maybe master else nee-master of a few, and definitely innovative with almost anything. (Hey man, I even invented recordable CDs LOL. Not quite in practice, but that's story I wrote hereon ages ago.)


** - PS: "waLkers" with an N is not considered an offensive term here, but it was auto-filtered by forum scrubber.