Amp may be bad?

[GaresTaylan 10+ year member]

System is listed in my sig. Got it all set up this past weekend with the help of Ng. Props to him for the help. Issue is, I have alt whine. Yes, I have browsed the threads on engine whine.

1) All amps share the same ground

2) Power wire/RCA's ran down opposing sides

3) Ran a ground from the HU back to the ground for the amps, no change

4) Turned the input on the 4-channel down to zero.. still have some whine

5) Disconnected the sub/amp, still have whine

6) Ran a new pair of RCA's back real quick. Current and new pair have great shielding, no change

7) Tried to ground the RCAs to the chassis of the HU, no change

8) Hooked up a GLI just for giggles, made the whine worse

At this stage (unless I am mistaken) I am thinking HU or amp. HU is brand new and yes I know it can be defective out of the box. I was thinking it was the amp bc in my last vehicle I had my Eclipse CD7000 hooked up with the same amp and had alt whine. When I replaced it with a CD7100 I ran into the exact same issue.

Eclipse wants $175 for repair, and there is a local place that can take a look for $30 and then $30 goes toward repair. Downside about all this is that I don't currently have access to a replacement amp or another HU to test both of those. Ng knows his stuff, so I dont question that its his install at all. Any other ideas or do I pretty much have it covered?

Click to read more...

 

[Horsemanwill 10+ year member]

if you ahve a portable cd player get a 3.5mini to rca adaptor and connect that directly into the amp while in the car see if that makes the noise go away, if not try an alternate power source first with the deck providing the rcas if noise is still there then try the 3.5 to rca. if noise still there it's the amp. if it's the xa4000 i'd suggest paying the 175 for repair it'll probably go to united radio the authorized repair center usually they just send u a different one back they did for me when i had issues on my ea2000. but they also give u a one year warrenty when u get it back.

 

[GaresTaylan 10+ year member]

if you ahve a portable cd player get a 3.5mini to rca adaptor and connect that directly into the amp while in the car see if that makes the noise go away, if not try an alternate power source first with the deck providing the rcas if noise is still there then try the 3.5 to rca. if noise still there it's the amp. if it's the xa4000 i'd suggest paying the 175 for repair it'll probably go to united radio the authorized repair center usually they just send u a different one back they did for me when i had issues on my ea2000. but they also give u a one year warrenty when u get it back.

You actually read my mind while I was out today. I used my brother's Nexus and plugged it into the front rca's on the 4-ch amp. Low and behold... the noise went away! So that eliminates the amp it would see. Thank you for the feedback on this.

Just for giggles I had a noise filter that I ran in line behind the head unit. That didnt fix the issue either. So.. sounds like it would either be the head unit or install related, correct?

 

[Horsemanwill 10+ year member]

correct to eliminate the hu take it out of the vehicle and put it next to the amp and see what happens.

 

[GaresTaylan 10+ year member]

correct to eliminate the hu take it out of the vehicle and put it next to the amp and see what happens.

I must be more retarded than I thought. I don't follow you on this one.

 

[Horsemanwill 10+ year member]

power up the hu outside the vehicle. then run the rca to the amp

 

[x2o 10+ year member]

Considering you said it happened on various HU's (CD7000 and CD7100), I'm thinking it's in the way you are installing the HU.

I'm guessing you used the same chassis ground or the factory ground when installing both HU's, try finding a different grounding spot. That would be my first guess.

 

[GaresTaylan 10+ year member]

power up the hu outside the vehicle. then run the rca to the amp

I will have to give this a shot tonight if I have time. Thanks.

Considering you said it happened on various HU's (CD7000 and CD7100), I'm thinking it's in the way you are installing the HU.
I'm guessing you used the same chassis ground or the factory ground when installing both HU's, try finding a different grounding spot. That would be my first guess.

I have tried running new grounds for the HU including back to the ground that the amps use.