car stereo/alt. question

QueBert

Lifer
Jan 6, 2002
22,946
1,138
126
My stereo is causing my lights to dim badly, I know it's really hard on the Altinator, but I don't have the cash for a HO one. I'm thinking about putting a 2nd battery in my trunk, running it to the main battery and running all my stereo stuff to it. Is this a good work around? I've heard it can cause troubles too...

thanks
 

ribbon13

Diamond Member
Feb 1, 2005
9,343
0
0
No. Just like stiffening caps, it's not exactly free power. You need a stronger alternator.
 

DaTT

Garage Moderator
Moderator
Feb 13, 2003
13,295
121
106
A second battery would be useful for high powered systems....which I doubt yours is.
 

QueBert

Lifer
Jan 6, 2002
22,946
1,138
126
Originally posted by: DaTT
A second battery would be useful for high powered systems....which I doubt yours is.

depends on what you consider high power. I'm running about 1400 watts. When I turn it up around 1/2 volume and a song with deep bass hits, the inside lights will dim almost completly out.

I have a 2000 Taurus which has a big battery, and comes with a larger then usual altinator.
I know it's not powerful enough to need a 2nd battery, but it would be much cheaper then adding a HO alt. I think I'll shoot for the Big 3, seems like a lot of work for a lazy ass like me though :)


I definitely need something
 

Viperoni

Lifer
Jan 4, 2000
11,084
1
71
1400 REAL watts?

You should be running a 1/0g power cable to the trunk, and definetely improve grounding underhood to the battery.

Another battery in the trunk would certainly help with dimming lights, but it wouldn't solve the problem of lacking current to properly support the power draw ;)
 

SwiftWind

Platinum Member
Sep 27, 2004
2,588
22
91
1400w is overkill...I would suggest a 1 farad cap if you are extremely tight on money and under 1k watt but...I suggest getting a bigger alternator before you kill this one.
 

b0mbrman

Lifer
Jun 1, 2001
29,470
1
81
Originally posted by: SwiftWind
1400w is overkill...I would suggest a 1 farad cap if you are extremely tight on money and under 1k watt but...I suggest getting a bigger alternator before you kill this one.

Bah...caps are band aids. Just upgrade the alternator
 

yokomo

Golden Member
Oct 18, 2000
1,275
0
71
Swiftwind said it you need a good cap that can hold the voltage steady when it really draws power.. but if the alt. dies then you go no tunez and no ride... you make the choice..
 

BigPoppa

Golden Member
Oct 9, 1999
1,930
0
0
Caps are a waste of money, imo. A bigger battery is just going to delay how long it takes your lights to dim on a full charge. If you bump full time, your battery(s) won't be charged enough in the first place. Like suggested, upgrade the big 3, buy a new alternator, or get a smaller amp. 1400 watts? Are you running a class D amp at 1 ohm? Dropping down to 700 watts would reduce your output by ~3db while halving the load presented to your car's charging system.
 

cjgallen

Diamond Member
Jan 20, 2003
6,419
0
0
Originally posted by: QueBert
My stereo is causing my lights to dim badly, I know it's really hard on the Altinator, but I don't have the cash for a HO one. I'm thinking about putting a 2nd battery in my trunk, running it to the main battery and running all my stereo stuff to it. Is this a good work around? I've heard it can cause troubles too...

thanks

2nd battery will make it worse. Your alternator will have to charge two batteries instead of one :p

Get a better alternator.
 

QueBert

Lifer
Jan 6, 2002
22,946
1,138
126
I don't have the money for an HO Alternator, if the Big 3 upgrade doesn't help I'll just ditch the Mono amp untill I have cash for the alt
 

BigPoppa

Golden Member
Oct 9, 1999
1,930
0
0
Originally posted by: ribbon13
Why not just turn the amp down until you can afford it?

How high is the gain on your amp? Can do some adjustment by turning it down.
 

jamesbond007

Diamond Member
Dec 21, 2000
5,280
0
71
I personally chose to install a 2 farad Tsunami cap in my car. I'm running an Alpine M501 550W@2ohms (d-class mono amp) and an Alpine F540 (80Wx4@4ohm). Both of those specs are RMS and the F540 is 700W max...not sure about max power on the M501, but it's plenty for my JL W3v2D4. It's not an insane amount of power, considering it's all in a 2003 Neon SXT, but it fits the bill. :p

I've had my system tested and at about volume 24/35max I hit 130dB. (maxed the meter). Why do you need to go louder? :p Do you feel like going deaf? ;)

Exactly what speakers are you driving? I run all Boston interiors and have a single 12" JL sub. Are you trying for competition?

EDIT: I should add that my lights don't dim much until I go over volume 20. I don't listen to it loud because I appreciate great sound and also my ears, too. This is why I chose a cap instead of a more expensive alternator.
 

QueBert

Lifer
Jan 6, 2002
22,946
1,138
126
Originally posted by: nourdmrolNMT1
hehe, underrated kicker amps....

i found that funny.

MIKE

Kicker's are almost always underrated, my old 1200 watt's birthsheet was at 1324.
 

MikeMike

Lifer
Feb 6, 2000
45,885
66
91
Originally posted by: QueBert
Originally posted by: nourdmrolNMT1
hehe, underrated kicker amps....

i found that funny.

MIKE

Kicker's are almost always underrated, my old 1200 watt's birthsheet was at 1324.

it depends, are you talking about the crappy BB stuff, or are you getting their higher end stuff?

and 1324 on what, with what? 14.4 volts, on a transistor, or what?

MIKE
 

QueBert

Lifer
Jan 6, 2002
22,946
1,138
126
Originally posted by: jamesbond007
I personally chose to install a 2 farad Tsunami cap in my car. I'm running an Alpine M501 550W@2ohms (d-class mono amp) and an Alpine F540 (80Wx4@4ohm). Both of those specs are RMS and the F540 is 700W max...not sure about max power on the M501, but it's plenty for my JL W3v2D4. It's not an insane amount of power, considering it's all in a 2003 Neon SXT, but it fits the bill. :p

I've had my system tested and at about volume 24/35max I hit 130dB. (maxed the meter). Why do you need to go louder? :p Do you feel like going deaf? ;)

Exactly what speakers are you driving? I run all Boston interiors and have a single 12" JL sub. Are you trying for competition?

EDIT: I should add that my lights don't dim much until I go over volume 20. I don't listen to it loud because I appreciate great sound and also my ears, too. This is why I chose a cap instead of a more expensive alternator.

I'm not trying to go deaf, or enter competitions. I'm running Polk Momo Comp's for my front, Infinity 5x7 rear. And 2 Atomic 12" subs. I doubt I could hit anywhere close to 130, but I know at 3/4 volume my head hurts. I don't want to go the cap route, it will get rid of my dimming, but it just masks the problem. My Alternator will still be straining and it will die just as fast. I'm trying to prevent that from happening :)

 

jamesbond007

Diamond Member
Dec 21, 2000
5,280
0
71
Is having a powerful stereo hooked up to your alternator a big strain all the time or only when it is loud and the bass is pumping?

If that's the case and that the cap is only masking an issue, perhaps I should look at a new alternator as well? :(
 

QueBert

Lifer
Jan 6, 2002
22,946
1,138
126
Originally posted by: jamesbond007
Is having a powerful stereo hooked up to your alternator a big strain all the time or only when it is loud and the bass is pumping?

If that's the case and that the cap is only masking an issue, perhaps I should look at a new alternator as well? :(

it's only a strain when the music is loud, it gets worse with more bass. I listen to Hip-Hop, and if I turn my deck up enough when it's dark outside, people can follow the beat by watching my lights flicker with each bass hit.

I'm not a car audio, or electical expert, but nobody with real car audio knowledge I've spoke to has ever suggested caps as a good, or even decent solution. They're more of a band-aid. And if anything will make things worse, because if you don't see the effects of the strain (lights dimming etc) you'll probably not worry or think about it, and keep playing the music loud.