First let me say hi, as it's my first thread here. This forum has helped me out with previous audio issues.
Just installed a Power Acoustik PDN626B head unit my '06 Corvette with factory Bose 7 speaker.
Using factory Bose amp. Just have a new HU. Yes I know, not a high end unit and I should ditch the Bose amp. Maybe later on.
Getting some nasty alternator whine with the new HU, but not the factory HU.
Low level outputs of new HU are soldered right into the factory radio harness. From there to the amp, the factory bundle of low level cables are shielded.
For some reason, I ONLY get the whine when I have the right front amp signal cable plugged into HU. I switch it and plug it into the front left, rear left, or rear right of the HU and still get whine. So it isn't HU output specific. It's specific to the amp's right front input. I even tried running a separate line from my new HU's right front directly to the amp's input harness.
That being said, the whine completely goes away when I plug the factory HU back in. To the same plug that my new HU is plugged into.
Amp is grounded through it's factory harness. I've also tried adding another ground from the amp casing to the battery.
Head unit is grounded to the frame. Have tried it through the harness, as well as the battery. Also tried constant +12v direct to the battery.
tl;dr
Old head unit into factory harness = No whine
New HU into factory harness = Whine
Unplug amp's FR low level in = No whine
Plug amp's FR low level into any HU output = Whine
I've attached a picture drawn by a 1st grader that tries to illustrate the issue.
Thank you in advance for any input.
Just installed a Power Acoustik PDN626B head unit my '06 Corvette with factory Bose 7 speaker.
Using factory Bose amp. Just have a new HU. Yes I know, not a high end unit and I should ditch the Bose amp. Maybe later on.
Getting some nasty alternator whine with the new HU, but not the factory HU.
Low level outputs of new HU are soldered right into the factory radio harness. From there to the amp, the factory bundle of low level cables are shielded.
For some reason, I ONLY get the whine when I have the right front amp signal cable plugged into HU. I switch it and plug it into the front left, rear left, or rear right of the HU and still get whine. So it isn't HU output specific. It's specific to the amp's right front input. I even tried running a separate line from my new HU's right front directly to the amp's input harness.
That being said, the whine completely goes away when I plug the factory HU back in. To the same plug that my new HU is plugged into.
Amp is grounded through it's factory harness. I've also tried adding another ground from the amp casing to the battery.
Head unit is grounded to the frame. Have tried it through the harness, as well as the battery. Also tried constant +12v direct to the battery.
tl;dr
Old head unit into factory harness = No whine
New HU into factory harness = Whine
Unplug amp's FR low level in = No whine
Plug amp's FR low level into any HU output = Whine
I've attached a picture drawn by a 1st grader that tries to illustrate the issue.
Thank you in advance for any input.
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