Ground Loops
 

Hey so I am familiar with what a ground loop is. (different resistance on the ground of two separate components in the same circuit)



My question is how much of a difference does it take to produce noise?

my HU and my amp have a resistance difference of 0.02 ohms.

I would think it's irrelevant at that degree of resistance, but then again, I'm still grasping the ropes on some things.



Thanks in advance guys

The long and short answer are both "it depends".



If you are listening to 10mV signals it will take less noise on the leads to be noisy than if you are listening to 1V signals. If your equipment has better power supplies, it will take more noise to influence the output. If your car is rolling it will be noisier inside, so your induced noise will have to be worse to be heard.