Lights dimming from 500 watts?

[JL12W7INAGS300 10+ year member]

I just installed a JL 500/1 Amp with a JL 12 W7 in a ported box in my lexus GS300. The battery is not stock, but it has the same specs as a stock battery. I used 4 gauge JL wire. When the sub hits the hardest, my lights have a slight but noticiable dim. What should I do about this? I am planning on getting a 1000/1 soon because the sub isn't hitting as hard as I would like. Thanks!

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[audiolife 5,000+ posts]

check the grounds and alt

 

[helotaxi 5,000+ posts]

To produce 500W with an 80% efficiency, the amp will draw about 45A @ 14V. Chances are that your alt doesn't have that kind of headroom, first, and it needs time to adjust its output, second, and the amp isn't that efficient, third. Depending on current draw, you can dim the lights with a lot less power than that. First thing is to make sure that your charging system is healthy. If you want to go to up to a 1000/1 you should be shopping for a bigger alt, as well. Adding a battery with a high surface voltage might help a little with the dimming from there as might a good sized cap.

 

[Ell 10+ year member]

Get a capacatator to help out the battery

 

[Ell 10+ year member]

Capacitor**

 

[Chevyaudio 5,000+ posts]

A capacitor won't help...probably would hurt.

 

[Ell 10+ year member]

Why do you say that?

 

[Blunt 10+ year member]

because they are not very efficient and yes they stablize voltage but at lower then what you want.

 

[Chevyaudio 5,000+ posts]

Because in most cases capcitors are useless for power stiffening purposes...and they create an extra load on the charging system of the car. The only decent caps for power stiffening purposes are those with Low ESR and ESL

 

[Ell 10+ year member]

Alright, makes sense.

 

[thugpassion 10+ year member]

because they are not very efficient and yes they stablize voltage but at lower then what you want.

my mobile spec 3 farad cap is consistantly 13.8-14.2v with techno on, music at low volumes its up to 14.4 so for that reason i must disagree. not trying to start an argument just sharing my results.

Caps are deffinately not an alternative to HO alts. If your stepping up toa 1000/1 you should deff look into an HO Alt.