Good voltage...but it drops low!

[bmuhammad1]

I have a problem with my voltage dropping WAY to low of bass notes. My voltage is good, hovering around 14.8-15.1 but when the bass notes hit at high volume I'm dropping down to 10.8-11.3v on certain notes. This is what I have and done so far...

(2) JLHD 600/4

(2) JLHD 1200/1

(2) 13.5 W7 in sealed box

Alpine DVA 800

Alpine PXA 800

H.O. Alt w/adj regulator 230 amp maybe 180 or so at idle...haven't had it measure

Two 0gauge per leads ran front to back to aluminum bus bar for all amps

Two 0gAuge grounds in rear. One connected to seat belt post under seat. The other to rear right quarter panel

I have also done the big 3 with clean connections

At this point I'm at a loss what to do or how to fix the issue. I'm going to try to change my ground connections to the frame of the car but that will entail cutting a hole in the trunk.

Just wondering if this great resource of knowledge will yield me any help for results.

[2000TACO]

check grounds and what battery do you have?

[Bump4life]

grounds may not be good.

what brand alternator?

only 1 battery?

[Kyblack76]

High voltage doesnt mean good BACKED amperage. You could turn it up to 25 volt, but you need backing.

Ill go out on a limb and say that HO alt you got, is something off ebay? or a "place" in town rebuilt it for you?

[pioneerforlife]

if you only have the stock batt under the hood than you don't have enough amperage. you really don't have any buffer between your system and the alt so it is pulling everything it can from that alt. that brand alt is it?

[JEFFYBOI]

You need more capacity. Its sucking up what little power you have stored real quick. You got the the power source ( alt) You got the wire upgraded to prevent voltage drop, but your your missing capacity. You need to have reserved or stored power. More batteries.

[bmuhammad1]

Oh I forgot to mention I have two stinger SPV70 batts under the hood... No factory battery.

[MrSkippyJ]

what kind of alt? I would take a guess and say either your alt isn't doing what you think or you have connection problems

[never knows best]

op- when you say the alt hasn't been tested leads me to believe that may be the issue as alternator manufactures should supply accurate spec sheets with their product... beyond that check all connections (sounds like you got this handled). if the issue still persists a larger batt bank or a cap bank wouldn't hurt.

[Robert8252]

Those JL amps put out some awesome power, your amps alone are probably pulling 250-300 amps at full tilt and your car still pulls it own amperage after that so you're asking a 230 amp alt and those batteries to supply in the range of 350 amps. The alt wouldn't keep up with that at 3,000rpm. I would put a D3100 in the trunk and start there, no matter what batteries will only keep you in the 12's but it will be a good start and much safer for your vehicle.