Humming in speakers with new radio
 

Anyone experience a low buzz/humming in their speakers after installing a headunit? I can hear it with the motor off and it doesn't change with the volume. I used the metra 70-1730 harness and everything is hooked up correctly.

Check to see if your unit is properly grounded.

I can almost guarantee it's a ground issue. Base or Tech?

It's a base. There are some civic and accord guys having the same issue. Something with balanced/unbalanced preamps.
It's not that noticeable when the car is on. Maybe I'll upgrade to a 5 channel amp down the road.

EDIT: I think i might have to ground the outer ring of the preamp RCAs to the head units chassis. This has helped some people.

Ah yes the balanced inputs (floating ground)... great choice for SQ but if you don't have the right set up it will be a problem. You may need to get a ground loop isolator to get the buzz out...

Yeah that's what I ended up doing. Got two ground loop isolators and buzz is mostly gone. It was real bad when I turned on my hids.

No problems with my JVC unit

I guess JVC>Android

Lol yea really? Do you really want to compare your expensive and restrictive jvc head unit to my android powered head unit?

... but does it hum? :shark:

Not anymore. After some reading, turns out it's the factory amp and or wiring causing all this noise. After some tweaking, the noise is gone. As much as I don't like android, it's the best OS to have in the car!

Interesting. Could you be more specific on the tweaking?

After I installed the isolators, I would say that 98% of the noise was gone. I moved the actual isolators and their ground wires away from any chassis ground and 99% of the noise was gone. I was also able to get rid of it by tuning down the high pass in the radio eq but that would of sacrificed the quality of the audio so I didn't do that.
The head unit also allowed me to raise the voltage of the preouts so I did that too and now the noise is pretty much gone. Luckily raising the output of the preamp didn't raise the level of the ground loop noise.

Basically, each one of your speakers have it's own dedicated floating ground wire (3 wires per) to accomodate a balanced signal that was coming from your OEM HU. Now that you have a low level signal coming from your HU it will cause issues due to the mismatch between source and speakers. Are you planning on upgrading the rest of your system?

You're exactly right sir. I do have plans to put in a 5 channel amp but not any time soon. I am currently happy with the way my stock amp/speakers sound now. Yes I know, hard to believe but the highs sound good and has very nice low bass. Good for now.

For now....it's a disease you know:ugh: