Ill be upgrading my sound system soon, i have the cobalt ss s/c and am wondering if i could maybe just get away by powering a 2000 watt amp with just a good secondary battery or if ill need a h/o alternator also to mantain a good voltage.

 

it all depends but ya you should be fine with just that. Make sure you upgrade the battery ground (s) as well as add an additional (fused) power wire run from the fuse box to the battery

 

The alternator charges the battery from it's natural resting voltage of ~12.4v to ~14.4v, so if you're trying to squeeze out the most power, you would want to have a higher output alternator. Upgrading the power line from the alternator to the battery is a good idea because the factory power line isn't very big.

 

Or build or have a bracket made for a 2nd alternator, and run a mechman dedicated to your system with one big agm battery dedicated as well. You'll hold 14.2 all day every day, up to 2400 watts stable. What db are you shooting for?

 

Idk i just basically want something louder then my jl w7 12 ah, i plan on getting a sundown zv4 12 and thinking bout getting a crescendo 2000 watt amp

 

Also another question, im looking at the crescendo Bc2000d and at 1 ohm its rated at 2250 watts at 13.8 volts, say if im seeing 12 volts for example will i not be getting the full 2250 watts out of it? Or does it not effect it.

 

correct

 

Not a cobalt but similar setup most likely. I have a Kicker KX 2400.1 in my Jeep. I have two runs of 2AWG running to a second battery (Deep cycle Marine Battery) then the second battery is double grounded to the chassis with 2 more 2AWG wires. I also have the Big 3 done (Really Big 4 as I ran a ground from the negative battery post to the alternator body and grounded the body of the alternator to the chassis). Voltage stays above 13.5V while engine is running no matter how high I turn it up. Voltage out of the alternator without the amp playing is 14.1V max not 14.4V like some put out.