I had a temporary run of 4gauge for my ground. It was just thrown there and grounded to an unsanded parts of my rear strut bracing. I would get a "thud" whenever I turned my system on/off.

I upgraded my ground to the same size as my power wire (1/0 gauge) and bolted it to a sanded part of the frame. Now my thud is gone.

This Ive heard is the usual culprit: Quoted from caraudiohelp.com

"Accessory Pop

Accessory pop is associated with one particular electrical event in the vehicle. This can be switching on your turn signal, headlights, brakes, windshield wipers or even the rear window defrost. These high current drawing accessories are causing a voltage spike that is traveling into your car audio equipment with the result being heard as a sharp pop. Adding a small bi-polar capacitor (0.47 uF) between the accessory's power wire and ground will often absorb these surges. You may need to place the capacitor on the load or the power side of the switch (maybe both). "

 

I get this pop too but i've had it in every system i've done and it's never made any other issues arise.. could those voltage spikes though have the potential to have negative impact later on? I have 8 gauge ground wire as i only have 50w rms from each amp...

 

Probably not, as a rule of thumb, you should make your grounds the same size of your power wire or bigger.