heavy voltage drop

[Cassix]

I have 2 12s being pushed by a 1500 w amp and my mids and Highs are being run by 400 watt amp. Every time the bass hits I have a voltage drop. If I play my stereo hard and continuous for about 5 minutes It'll slowly drop more and more and more until it's hitting between 11 and 12 sometimes drops below 11 and my battery light comes on in my truck. I'm not sure how to fix this besides getting a higher amp alternator. My alternator right now is 136 amp in my Dakota. I've done the Big 3 upgrade and I have a yellow top Optima. I have a 12-volt auxiliary battery connected to my sub amp. It's one of those small ones that look like they're going to lawn mower. I have a 6 gauge run from a battery back to my amps and then everywhere else in the truck is 0 gauge. I don't know if this matters but I upgraded my door speaker wires to 12 gauge running straight from my amp which is a JBL gx-a604. I have my two Sundown Audio 12 wired down to .5 ohms. And have a Sundown Audio sa e 1500 pushing my Subs. I'm trying to give all the information I can so you guys can have all the information you need to give me proper guidance. So if I'm all over the place that's why. I think that might be it if anybody has any questions let me know but if you guys could help me or give me any suggestions that be great but I have a feeling I'm going to have to upgrade my alternator. Another thing is my headlights never Dim when the bass hits but my dash lights do. So if anybody has any ideas I appreciate your time

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[poolman966554]

how old is your battery? You would probably have even worse voltage drop if you had proper sized power wire. 6 gauge is not enough. you need a minimum of quality 4 gauge ofc, not cca.

Hows your ground wire installed?

 

[THATpurpleKUSH 5,000+ posts]

Why would you run 6gauge power wire to the rear? That size cable can only handle about 1/3 of the current that your amps need. That is your problem right there, upgrade that small auxilary to a full size agm too.

You should run 0g to the back battery. Even 4ga won't handle all that current.

Also look for an ho alt

 

[shredder2]

I have 2 12s being pushed by a 1500 w amp and my mids and Highs are being run by 400 watt amp. Every time the bass hits I have a voltage drop. If I play my stereo hard and continuous for about 5 minutes It'll slowly drop more and more and more until it's hitting between 11 and 12 sometimes drops below 11 and my battery light comes on in my truck. I'm not sure how to fix this besides getting a higher amp alternator. My alternator right now is 136 amp in my Dakota. I've done the Big 3 upgrade and I have a yellow top Optima. I have a 12-volt auxiliary battery connected to my sub amp. It's one of those small ones that look like they're going to lawn mower. I have a 6 gauge run from a battery back to my amps and then everywhere else in the truck is 0 gauge. I don't know if this matters but I upgraded my door speaker wires to 12 gauge running straight from my amp which is a JBL gx-a604. I have my two Sundown Audio 12 wired down to .5 ohms. And have a Sundown Audio sae 1500 pushing my Subs. I'm trying to give all the information I can so you guys can have all the information you need to give me proper guidance. So if I'm all over the place that's why. I think that might be it if anybody has any questions let me know but if you guys could help me or give me any suggestions that be great but I have a feeling I'm going to have to upgrade my alternator. Another thing is my headlights never Dim when the bass hits but my dash lights do. So if anybody has any ideas I appreciate your time

Sounds like the wire from aux battery is undesized like the battery itself and the 136A alt is tryin' to keep up with a sae1500 at 1/2 ohm. Real aux batt with new wire to amps and a better alt if it persists dropping. That small battery is probably not helping much... IDK

 

[wew lad 5,000+ posts]

lol did no one tell you that wiring to .5 on stock electrical with small wires was a bad idea beforehand?..

 

[THATpurpleKUSH 5,000+ posts]

Especially with a Chinese amp, that thing is probably pulling 250a of current or more.

 

[Chris McNeeley]

I love how everyone thinks they gain a bunch wiring to .5, but very few consider the heavy loss of efficiency. Everything should be 1/0, cca is fine, get a cheap g31 agm to replace the small back battery, and guessing you don't charge to top off so get a cheap agm charger with a 2 amp trickle charge function and top off based on usage.