Anyone help here? after starting my car with the head unit OFF I hear a whine and then a loud THUD from all 5 speakers. After that thud everything sounds fine. I don't get this condition if I turn the car on with the radio on and there is no whine or other interference in the stereo except for this initial thud.

Setup:
Kenwood H/U
dual Alpine amps - simple setup split 4 g to 8 gauge, dual ground
no capacitor

 

Sounds like the noise from amp turn on but I'm pretty sure Kenwood and Alpine have built in amp turn on circuits to eliminate this. Maybe something wrong with one of them.

 

I was thinking about this too and maybe its my setup. On an earlier config I had tied my amp remote to the cigerette lighter output in the back there. It is still running off that lead and not from the head unit so when the car turns on, the amps turn on..whether the head unit is off or on.

SO, do you think by swapping the Remote ON lead to come from the head unit instead of the lighter it will take care of this?

Thanks again!

 

That would be the first place I would start. Maybe the amp is getting some sort of feedback loop or something by turning on with no signal. Worth a shot

 

Thanks everyone. One other thing..if your familiar with the cubby spave behind the driver seat -- I grounded each amp to the metal brackets that hang down from the top inside there..hopefully that's a proper ground point.

The Kenwood deck has a few extra hookups that have to do with using Kenwood Amps..I'm gonna read into these too.

 

^^ I have grounded my amp in the same spot. Make sure you use a dremel, or some high grit sand paper to sand off any paint on the metal tab, and get a clean ground point.

 

Thanks neur0sis, I scaped them with a razor but I need to do a better job.

 

nice call fellaz. After connecting the power lead from the head unit the noise went away...now I just wish this ringing in my ears would go away.........

 

LOL Glad you got it figured out. That was my first guess when i read your prob...