when i turn my car on i loose SPL vs. when the car is off.


it's a 4 banger, new alternator. with car on it charges at 14.4v

with car off voltage starts at about 12.7


ideas?

 

Daytime running lights fan other car accessories who knows lol

 

fan is off, lights are off. the only things that are on are the alternator and the engine.

 

car is stealing power from the amplifier so it will go faster

 

have you upgraded your cars ground wires? Eg, engine block ground, chassis ground, alt ground? if not, try that. are you running your amp ground to the body of the car or straight to the battery? check those things out and see if that helps.

 

explain why would any of that matter?

 

when your car is running all the current that your car is using has to run back to the battery through those little wires. adding more current with your amps and subs would be like adding a dam to a river. think of it this way. the electricity is water. Now, if you had 5 gallons of water, what would that 5 gallons of water run through faster, a funnel with a 2 inch hole, or one with 6 inches? It's the same thing with adding more current demands with your car, the small wires can only handle so much current before it gets backed up and only lets so much through.
So your car is probably directing more current to your engine and it's components, rather then your stereo.

 

Actually if his factory wires are small and he has 10+ runs of 0 awg to his amp then the car is directing more current to the amp instead of the engine, this situation still does not make sense. Should be louder with car on, by atleast a few tenths.

Dont forget however that your alternator is putting out about 60-70 amps MAX, and you are pulling 600-700+ AMPS of current, its not going to be a big difference if its running or not.

 

Here is more info. My voltage drop is more with the car on.