- Pyramid amp,
- 2 Alpine subs
- Cheapest alpine deck I could find.
After driving for a few minutes, the thump starts to happen. Also when it happens, I can hear a high pitch spinning when I rev tthe engine. They both happen simultaneously. But at very random times. It'll thump for 10 - 60 seconds, then stop for a few minutes.
I've never experiened this until I moved the ground for the amp. I moved it back to the original spot (when there were no problems.) but the thumping/engine humming persisted, so I sanded down the metal grounding the amp. (That didn't really solve much, it alleviated the problem though. Which doesn't make sense to me, because it was fine when I first installed it. It worked fine up until I decided to play with the ground)
The thumping/engine humming stops when I shut off the HU.
If it's worth mentioning, when I moved the amp ground, it apparently wasn't good enough (and caused the amp to heat up pretty quick. I started hearing thumping noises 5 minutes into driving, as soon as I heard it, I pulled over and swapped the ground to where it original was. Also... when I was messing with the wires, I had one sub in (+)(-) and the other in (-)(+) which canceled each other out. I didn't realize this until 20 minutes into driving.
Did I mess up bad? Do I need to ground the head unit? Do I need a new amp?