cap math?

red_parchel · 07-20-2006, 07:40 PM

alright, here's the deal, i've been doing simple stereo installs for myself and my friends for about 6 years now, i've learned a lot, and i feel i've come a long way, i've always gotten away w/o needing to use caps ... by using efficiant amps and matching the subs well .. well last year i ended up w/ some big equipment, and i've got it in my '00 blazer LT,

orion 2500D 2,500W RMS@1 Ohm driving a 1999 15" orion HCCA
orion 50 watts x 4 chan. @ 4 Ohms
200 watts x 4 chan. @ 2 Ohms
200 watts x 2 chan. @ 4 Ohms Bridged
driving 2 sets of memphis 15-MSYNC6 components
the sub hits hard [as it should w/ 2500 watts

but of COURSE the head lights "dim" ... now i know a cap isnt the "real" way out, i need a bigger altinator, [and prob a few caps] but for now i dont have the money to put in the kit Stinger [manufaturer of after market altinators] and local shops recomended

and this just isnt a good enviroment to put a car computer in.
for me another battery is not an option either for various reasons.

so i know this is getting long but .. the 2500D takes 2 4gauge power feeds, the 4004 takes a 4gauge input, i havent run the cabling to my pc yet b/c i need to get the power spikes undercontrol ... the QUESTION finally is would 3[one for each power line] 1or2 farad caps do the trick? [at least till i can pony up the 800+ for the altenators/install] - i know thing WAY bigger then this have been done, even here on this site [

]

thanks for the time reading this, i've gotten very mixed feelings on how to do this, hoping as a community i could get some good input here .. again thanks in advance!

stkdidy ntshidy · 07-20-2006, 08:27 PM

if you listen to bass-heavy music at reasonable volume, a cap will not help at all...and actually could decrease performance if never given a chance to charge up in between heavy hits. i recommend running 0/1awg wire back into a splitter (into 3 4awg all fused individually). put in an optima yellow top. save up for an alt, which can be custom made for well under $600. another option is to install a second alt, but i dont think you need that complication at this point

Shadow · 07-20-2006, 08:28 PM

Every single bit of money you would put toward buying a cap SHOULD be put towards upgrading your charging system or putting in an extra battery.

Caps don't work for car audio. Period.

pancit175 · 07-20-2006, 09:04 PM

A second battery would be more efficient and more cost effective than multiple amps

Shadow · 07-20-2006, 09:44 PM

If your full range amp is an HCCA amp, you need TWO batteries, not one. Class A/B amps like that draw a stupid amount of current.

red_parchel · 07-21-2006, 12:25 AM

Quote:

i recommend running 0/1awg wire back into a splitter (into 3 4awg all fused individually).

i ran 3 4awg wires b/c of space, i wanted to run the 0/1awg but it was just too damn big to hide *easily* in my blazer, as we know its not too flexable

Quote:

put in an optima yellow top. save up for an alt, which can be custom made for well under $600. another option is to install a second alt, but i dont think you need that complication at this point

the yellow top is on the list, next thing to get

the second alt was suggested by the local shop, but i just wasnt serious enough [they were talkin about takin out my a/c ... no way! ... but i think theres a new mounting bracket i wouldnt have to do that, but thats another story, ill poke around for custom altinators, any suggestions?

so now that caps are completely bashed from my mind on ward to the second battery questions... parrelelle? isolated? 2 batteries means much heavier load on the altinator [there's some law i learned in college that proved that] so that would lead to a bigger altinator .. i think im seeing a pattern

yes the 4004 is an a/b class amp ... a bit of good news is the 2500D is considered a class D amp ..

thnx for quick replys since im a new postee, been reading here for a long time tho

scott_fx · 07-21-2006, 03:23 AM

Quote: Originally Posted by Shadow

Caps don't work for car audio. Period.

my amps have caps inside of them

Shadow · 07-21-2006, 08:28 AM

First, it's an alternator not altinator. Second, you've got room under the hood for a second battery. Third, as long as you never sit with your car off and play the system, your factory alternator could handle the secondary battery no problem. I had a 100A GM Smallcase alt that handled a normal lead acid and two 1100CCA batteries just fine. Fourth, if you want to isolate the batteries, that's cool, but high amperage isolators cost a LOT of money. I'd just parallel them.

Red top = cranking battery
yellow top = battery for system

The yellow top is made to be deep cycled. With your alternator constantly charging it you'll see less benefit out of it. The red top is meant to be topped off most of the time.

XC-C30 · 07-21-2006, 08:33 AM

Quote: Originally Posted by Shadow

Caps don't work for car audio. Period.

is that why so many people use them?

and indeed, as scott said, that is probably why there are caps built inside an amp.

don't want to diss you, but it's a matter of environment. for a yer'allday install it could be usefull. in db-drag -you're right- they're a no no. and for SQ, don't think they are used alot also. but still, for an all day ev'ry day install it can be usefull because most of them people are not going to spend $$$ on a yellowtop or an alternator.

red_parchel · 07-21-2006, 08:58 AM

Quote:

First, it's an alternator not altinator. Second, you've got room under the hood for a second battery.

F7! ok so theres no spell check short cut .. sry 'bout that..

i've spent a good amount of time under the hood of my '00 blazer, and there is no room for a second battery, w/o major modification to the fender, and i still dont think i could fit it, it's gunna have to be in the "trunk" *more wire* now the early 90's blazers TONS of room

thanks for the info shadow ...

ya from what i've learned for a high currant drawing system a cap is not the way to go.

XC-C30 · 07-21-2006, 09:06 AM

you could also rewire your alternator. (at least let it)

RedGTiVR6 · 07-21-2006, 09:12 AM

I'd spend the money to have your alternator rewound. More power, same alternator.

I'd spend the money on a new battery, rewind the alternator, and find a way to run 1/0.

You can run it underneath the car, as long as it's in something that will protect it. Something like Flec-tite (flexible conduit that's liquid proof.)