Hey guys I recently installed a new Alpine 400W amp, JL Subwoofer, and 2 Boston Acoustics for the doors (RT/10). The sound is really good, but I get this engine whine when the car is on.
Now I'm aware of some ground looping problems and other electrical issues, but this is drivin me nuts... can't pin point it. /images/graemlins/freak
I'm using the stock Alpine head unit, which worked fine/no noise w/ the stock Viper's amp. I spliced the output wires from the HU to fit the input plug on the Alpine amp. The same for power/ground.
Some points:
The engine whine is only present when the car is on (duh)
The engine whine does not get louder with the stereo volume!!!
It does go up and down with the engine, so its prolly alternator noise
The gain on the amp is not past middle
When I unplug the HU inputs to the amp while the car is on, the noise is gone
This tells me the noise is being introduced somewhere between the HU and the amp (but prolly not in the HU itself). I took the wires, and did some temp insulation for EMI tests.. I wrapped the shielded HU wires in aluminum foil... didn't effect it at all.
The HU wires are really thin (factory wires). They were wrapped from the factory in shielding, which I have going to the ground lead on the amp (common). One other weird thing.. the HU has four outputs: front left, right; rear left, right. Front and rear left channels both share the same ground path, and the same for Front and rear right. I thought most HU's have a diff ground path for each of the four channels?
Now I'm aware of some ground looping problems and other electrical issues, but this is drivin me nuts... can't pin point it. /images/graemlins/freak
I'm using the stock Alpine head unit, which worked fine/no noise w/ the stock Viper's amp. I spliced the output wires from the HU to fit the input plug on the Alpine amp. The same for power/ground.
Some points:
The engine whine is only present when the car is on (duh)
The engine whine does not get louder with the stereo volume!!!
It does go up and down with the engine, so its prolly alternator noise
The gain on the amp is not past middle
When I unplug the HU inputs to the amp while the car is on, the noise is gone
This tells me the noise is being introduced somewhere between the HU and the amp (but prolly not in the HU itself). I took the wires, and did some temp insulation for EMI tests.. I wrapped the shielded HU wires in aluminum foil... didn't effect it at all.
The HU wires are really thin (factory wires). They were wrapped from the factory in shielding, which I have going to the ground lead on the amp (common). One other weird thing.. the HU has four outputs: front left, right; rear left, right. Front and rear left channels both share the same ground path, and the same for Front and rear right. I thought most HU's have a diff ground path for each of the four channels?