I received 2 12" Infinity subs, and a 750W MTX amp for my car when i got it [ a couple months ago ], and for Christmas my brother gave me new 3-way Pioneer's for the front doors and back deck
( i have a 2-door car. )

Lately I've been realizing that since i put those in, my headlights dont work at full brightness whenever i play music in my car, or at least when the bass is hitting
( This was sometimes noticeable when i just had the subs, but now with the extra current being drawn its more consistent.)
And I've been wanting to put 6" subs underneath my seats just for a little extra bump.

However , this would kill my battery power, I'm pretty sure.



My question is: Would it be better to get a capacitor hooked up in my system , or to get a separate battery just to run my speakers off of, (or a separate battery for just the door/backdeck/6" speakers)
once i put the 6" ones in.

I'm pretty new to the car electronics world, but i know quite a bit about electrical systems in general, so I'm not sure what the advantages of each would be.



By the way: I see a lot of people debating there asses off in this section, just from the couple of threads I've looked at. Please don't flame each other in here until i get a couple of level-headed answers.

Thanks!

This post was edited by BigBank on Jan 4 2012 04:31pm

what is your current battery?

what exactly do you mean? its my 12V car battery

deep cycle dry cell or regular wet cell, whats it amp rating? how old is it?

If you mean the CCA rating, its either 425 or 500, a wet cell battery, and idk how old, but i know i need a new one (getting it soon)

Although my battery is needing to be changed, before i hooked the inside speakers up, i was able to listen to music non-stop with the subs up very loud for 20-25 minutes w/o it dying,
with the new back deck and door speakers, i maybe have 5-10 minutes.

they require more power than your stock speakers its as simple as that.

get an optima yellow top. its a deep cycle dry cell and it will last much much longer than wet cell batteries.

but will it be able to power my lights, 2 12's , the new speakers on the inside, and 2 (or 4 possibly) 6" subs under my seats?
Thats what my original question was ; whats the best way to run all of that.

its more about rms watts than sub size. without knowing exactly how much rms you are wanting to run i can't give you a definitive answer. chances are an optima yellow top 750 model will be fine.

you will also need to do a big 3 upgrade in the future. http://forum.sounddomain.com/ubbthreads.php/ubb/showflat/Number/312025/page/1

another issue is going to be your alternator. if you can get its amp output i can tell how how many watts is too much for it.

If you have an old, shitty battery, it can require more amperage/time to recharge than a newer, good battery.

You also have to be careful when switching to a deep cycle battery because they provide less cold cranking amps than a regular battery. If you live in a cold climate I would suggest sticking with a normal battery (a good choice would be a red top optima battery).

A deep cycle battery will provide more reserve power, but in my opinion, it is unnecessary unless you are listening to your system a lot with the engine off. And again, I would be hesitant to completely replace your normal battery with a deep cycle battery...most people usually add in a deep cycle battery to their system to compliment their existing normal battery. If you do this, however, you must be careful to ensure that both batteries are in similar condition and you have an isolator between them.

To be honest with you, your system isn't something that would warrant either a deep cycle battery or an additional battery. Simply having one good regular battery and a cap should solve your dimming issues, and is probably the most cost effective way of solving the issue.

If you choose to upgrade your system in the future (eg adding more amps) then I would suggest as big three upgrade as well as an alternator upgrade.

Also, a 6" speaker is not a sub, it is a midrange driver...and will not provide "more bump." It would be more beneficial to tweak your existing system...eg switching to a ported box for your subs or getting a more powerful amp, or if your subs and amp are compatible, rewiring them to run at a lower resistance (eg 1 or 2 ohm if they aren't running at those resistances yet).



After reading this, it seems you have let your battery drain numerous times. When you do this to a normal car battery, you cause irreversible damage to the battery. This is probably why your headlights are dimming because your current battery is so damaged that the alternator has to put out more amperage to keep it charged and the battery cannot do a good job of assisting in voltage drops.

If you like to listen to music with the engine off to the point of draining your battery, then I would take Subwoofer's advice and switch to a deep cycle battery. But again, you have to be cautious when doing this because it will not be as good as a normal battery for starting your car.

he said his current battery cca was only 500 max so how is a 750 cca yellow top going to be worse?

there are plenty of 6 1/2 subs on the market. subs are about low frequency response not size.

red tops are cranking models. yellow tops are dual purpose models.

deep cycle dry cell fits his needs perfectly. he doesn't need more cca than a mid range yellow top. it will last a lot longer than a wet cell and end up costing much much less.

"adding more amps" is a bad way to give advice. he should focus on rms watts total in order to properly upgrade his electrical system to the correct specifications.