Subwoofer Thump when turning on/off and switching between source

[NancyDrew]

Well today I decided to upgrade my headunit with a DEH-P6000ub pioneer. After installing the HU, I got a horrible thump from my subwoofer's when I turned the HU off/on. It would also thump when I switched between source's, usb, cd, tuner etc.. Well years ago I had this issue and I could not remember how to fix it. So I cussed and cussed again. And its such a simple fix, you know the ones that drive you crazy trying to remember when you know the answer. And no it was not the remote wire causing the problem by turning the amps on to soon or off to late. It had nothing to do with all that. Nor was it grounding the rca's. And no it wasnt due to the amplifier not having a soft start, which it does. Its this simple folks. Run a Ground from the chasis to the back of the HU frame. I put two seperate grounds to two seperate screws on the frame of the HU. Guess what happened when I turned on the HU. NO THUMP. Nor did it thump when I swtched between source's. Hope this helps someone.

It's the simple things in life that really matters.....

[bbeljefe]

Yep. You should always have a good ground between the amplifiers and the head end equipment. Often, the steel panels and braces in the dash are poorly grounded or not grounded at all. When the latter is the case the head unit winds up getting its ground through the antenna with is also a poor ground.

It's good practice to always ground head end equipment to the chassis of the vehicle, even if you don't start out with a thump.