slowfkncar

Two 6v batteries? Or you meant 2 12v in parallel? One under the hood & one in the rear? Honestly a single 1/0 should be plenty for that amp, have you checked voltage at both battery terminals while playing at a moderate volume level?

What amp are you using bro? A drawing or picture of the wiring could help here. Are you pulling 300a+ out of single 2/0's?

Since one battery has 17x more discharge current than the other, I was under the impression that you already had a load tester. You could always swap the location of battery one with battery two, in theory if your crimp/wires are crap it will be the other battery that acts up. Fwiw, 9 times out of 10 this is simply a battery going bad, built enough resistance that it no longer has the same discharge output, but ive also seen people try to use a hammer or a shit crimper on 0 gauge, this normally causes problems when trying to pull 150+ amps through a half crimped ring.

Both a sulphated battery or loose crimp/connection at one of the terminals ect can cause similar symptoms. Without actually seeing your setup, load testing them individually is the easiest & fastest thing I can hint you as this will tell you right away by process of elimination. What amp are you running?

Charge them both again and load test them one by one, if both hold the same/similar output then check your crimps & wire.

For driving a relay, a 1 amp diode will work fine. *Any 12v light will work, up to 30A per relay.

1 diode & spdt relay. No parasitic draw & no feedback with a switch. For negative dome light trigger 30 = 12v output to light 87a = N/A 87 = 12v 85 = 12v 86 = negitive door trigger input & negative switched, diode isolate door trigger wire at relay. Anode side facing relay For positive dome light trigger 30 = 12v output to light 87a = N/A 87 = 12v 85 = ground 86 = positive door trigger input & positive switched, diode isolate door trigger wire at relay. Cathode side facing relay There are other ways to wire it up without a diode, but that depends on how much current your dome light circuit can provide, this is why i didnt show 87a.

The sound quality & sensitivity difference is huge, sure the smaller tweeter would sound better but you are likely not going to hear it over a pro audio tweet.

Can't speak for the nvx loc, but I personally prefer the way lc2i's sound when using the active subwoofer outputs from factory amps. Those outputs are usually pre-equalised, accubass can help flatten that.

The amp in slave config usually doesnt respond to the phase/gain/xover settings, that's what the slave/master switch is for.

My first active setup back in the day was A/6/S 641's, you should have seen how many holes i cut for my midrange until i got it right lmao.. It took me a couple months of just settings and driver location alone. When you go active, especially moving from a high end passive crossover to digital, you are removing certain things that could hurt certain setups. The Q of the set is altered, the woofer/mid phase gets set back to 0, the tweet resistor gone, requiring a MUCH smaller amp, you might have bypassed a baffle step and/or zobel circuit ect.. Depending on the drivers capability and how well it plays in your vehicle, sometimes you need to compromise for these things.

The xdi v2 is nice, just keep it away from your antenna/ant cables ect as it can reduce reception and/or introduce FM interference. not only is it a ton of power for your midrange/tweets its also full power from 2-4 ohms, you would need to be VERY careful with that on your BPF/HPF drivers.

You might have one hell of a time finding a 6 channel a/b with DSP that will fit under a front seat, most of us with limited space run a 4+2 or 2+2+2 for our 3 way fronts, morel are some of my favorite budget amps for SQ along with arc and zapco, I'd hate to run low s/n amps with hat drivers in active.

Good quality 1/0 is good enough for your 200A musical draw, the problem is you would need to give the main fuse a little more headroom due to the 4 channel on the same line and that's really not a good idea in terms of protection for daily driving, (e.g) rare but, you don't want a 200A dead short on a 250A fuse. A small battery or some type of block/bar/distributor in the rear would allow you to fuse the amps independently.

First thing i would do is make sure the electrical under the hood hasn't been messed with (battery terminals,big 3,grounds ect). The shop that did your a/c could have unplugged the battery which might have reset the head unit into different settings.