[NH Ben]

I'm transplanting 2 amplifiers that I've been running in my Aveo into my 2016.5 Cruze and now have a new noise issue. It's electrical noise that is not engine rpm related. Everything sounds good with the key "on", but when I start the engine, there is a persistent noise like an AM station that isn't coming in. The noise doesn't get louder or quieter with the volume and does not change with rpm. When I shut off the engine, the noise remains for another 30 seconds or so until the car's computers and controllers shut themselves off then the sound is good again. I've powered the amps with both an LOC and amplifier self turn on. I've run power directly to the battery to avoid the car's circuits and still no change. I can bypass the amps completely (with speaker wires in the same locations in respect to the power wires) and then the sound is fine, just not amplified. Turning the gains on the amps all the way down gets rid of most of the noise, but limits my set-up. I've tried shielded and twisted pair RCAs. What am I missing here?

 

[brian v]

Are your signal leads too close to the + or - power inputs ? If so you are getting feed back . Check your your grounding point for a clean complete contact point .. good luck with your trouble shooting .

 

[NH Ben]

Well, I did a little more troubleshooting. Re-routing the signal wires didn't make any difference. What I did do is run RCAs from another car to the inputs of my amp and everything sounded fine. So right now I have speaker wires from my dash going to an LOC in the trunk. The LOC has RCAs and amp turn-on lead coming out. I'm using that lead to turn on the amp. RCAs from the LOC to the amp make noise. RCAs from the other car to my amp are quiet. I even purposely ran the RCAs from the other car right on top of battery power with no noise. Does my factory head unit just not like to be amplified? I really didn't want to mess with the dash.

 

[ChevyGuy]

I'd try a different LOC. Either it's a crummy LOC that's not isolating ground noise, or some magnetic noise is getting coupled into it (perhaps something from the amp itself).

 

[NH Ben]

Update: I've been just listening to the stereo as-is for a few weeks, but decided to try rewiring as an experiment yesterday. Running the rear speaker wires only into my amp, I can amplify just the left or just the right with no noise. When I connect inputs to both left and right I get that noise again. I can split the inputs with a "Y" and run all 4 channels (and my sub amp) no problem. I just don't get left/right stereo.

 

[ChevyGuy]

I can amplify just the left or just the right with no noise. When I connect inputs to both left and right I get that noise again. I can split the inputs with a "Y" and run all 4 channels (and my sub amp) no problem. I just don't get left/right stereo.

Interesting. Clearly there's some kind of noise between the channels, or perhaps some kind of lack of isolation between the inputs in the amp.

 

[anthonysmith93]

I had a cheap LOC do that, if I had both left and right hooked up it made a buzz/hum sound, but if I only used one side (either one) it was fine. I ran off one side for a while and it completely stopped working eventually, replaced it and problem fixed.

 

[deliad]

Hi did you found a solution? I Have the EXACT Problem you experiencing on my Mexico Made 2017 Chevrolet Cruze Premier

I have Pioneer D9604 Amplifier which has internal LOC for the chevy 7 inch radio, also with the chevy i have the same problem

I also Have the same when i use my Aftermarket radio connected to the car power with RCA signal

My amp is connected to the battery positive and directly to main car negative screw.

I also tried to connect the amp negative to the negative pole of the battery directly, i know its the same but no change at all.

When turn off i have that anoying noise and after 30-60 seconds when some system shuts off, everything is fine and clear,

Please send me PM we Can Solve it together

I'm sure that its some system that makes the power or the negative, not clear for the amp while the car is running and untill that system shutdown.

Tried to run positve with 10 amp fuse and a negtive wire to the radio (so the amp and the radio shares the same power source), no change.

Ofcourse when i connect my phone 3.5mm for example, which is not powered by the car circuit, no noise at all