I did a search, but I didnt find anything on this. This is really just a general car question. I installed two 12s in my trunk about a year ago running a kenwood 600 amp to them. About three months ago, my alternator went out and i had it replaced. I figured, 7 year old car= old alternator. Two days ago, it went out again. I think I'm drawing too many amps off my battery and its wearing out my alternator. Im looking into getting a higher amprage battery. Any suggestions on where is the best place? or what is the best configuration. should i get two batteries and put one of those car audio batteries in the trunk separate of my alternator and my car battery? any help=

 

Where did you get the alternator from? A while back I went through 4 AutoZone alternators on my old Aerostar before I got a good one. Their "lifetime" warranty doesn't mean much when you have to constantly re-do the labor. The quality of rebuilt parts has been really $hitty the last 10 years.

I don't know much about audio systems, but I don't think a higher cranking-amp battery will do you any good.

 

I got all the work done at the normal place i get all my work done. They usually do a really good job whenever they work on my car, but i dont know where they got the alternator from. I just want to know if there is anything i can do to prevent this from happening every couple of months. I dont want to pay all that labor!

 

I agree with sinewave that a higher amperage battery probably won't help since you are probably draining the battery and then straining the alternator. You mentioned that you have two 12s, but you didn't specify what kind or how many Watts your system is.
That makes a big difference because my JL 12W0 only pulls 150W compared to the (high) wattage that a JL12W7 pulls. An audio store might be able to help you more, or you may just need to get a capacitor (cap) to help out your alternator.
-hype

 

i have two oldschool rockford fosgates punch xlc's- they are 200w speakers each running only about 150 a piece off a kenwood 600 amp. what can a capaciter do for me?

 

ca·pac·i·tor (k-ps-tr)
n.
An electric circuit element used to store charge temporarily, consisting in general of two metallic plates separated and insulated from each other by a dielectric. Also called condenser.

Basically the cap is used to flatten out the spikes that your subs can cause while drawing current. I believe this is what usually kills alternators because it intermittently strains them over time (that's just my guess though), but in most powerful systems you will see a 1/2 Farad or a Farad cap.
-hype

 

That doesn't sound like a huge draw, I'd think the max would be able to take it. A cap could help in that situation, as it takes some of the strain away from your electrical system by supplying a reserve for when the power draw/stereo peaks. Also, I'm not sure what model Kenwood amp you're referring to, but something else you could look at before buying a high-priced hi-performance alternator or somethign among those lines is a new amp. If your Kenwood is a class A/B/hybrid amp, switching to a class D amp will help your power system out, as it would be able to output the same amount of power more efficiently without straining the electrical system of the car as much.

electronics whizzes, feel free to correct me if needed or explain things a little more thoroughly.

 

Maybe it was a combination of weak tired battery and strained system which made the ALT give out. How old is the battery? Replace the battery next time, not necessarily with a higher output one. And, like the others said, add a cap.

DW

 

I better not screw myself saying this, but I have not had any alternator trouble in either of my cars that I had my stereo in. I'm running a Soundstream Rubicon 1000.2 (1000 watts), a Rockford A500II (about 125x2) and a Hifonics Mercury X amp (80x2) all on a double grounded optima yellow and stock alternator. My old toyota camry 4 cyl's alternator was OK until 155K miles and that thing took a beating.