Stereo interference

[sedgu]

Hey, a while ago my stereo began to get interference from the fuel pump and when the car's turned on a whining noise (from speakers) gets higher pitched the higher the rpm's, and changing gears. I recently ripped the dash out to replace it and checked all the headunit wires, properly insulated and grounded them etc. The culprit appears to be the amp, but I really can't see anything wrong with the wiring etc. What should I be looking for before I end up spending more than I should? havent had muzak for months D:

[13bwankel]

I'd suggest you have the amp rca's running down the same side of the car as the fuel pump power cable (or amp power cable) try reversing the setup you currently have first.

Could also be your altinator... perhaps?

[gotorx7]

Biggest source of interference for me is the constant whining from the passenger seat.

Unless I leave her at home, of course :)

You could hit Jaycar up for some Toroids and run your power cables through them. Depending on where the noise is actually getting in, it may or not fix it, but that would be one less possibility.

Even better, pull all that crap out and save some weight! Sell it all off and buy an iPod!!

[capella re]

Biggest source of interference for me is the constant whining from the passenger seat.

Unless I leave her at home, of course :)



Geez, hope your misses doesn't visit this site or the interference could be a slap to the head!!!

[[ANG_RE]]

My mates car does the pitch with revs thing, pretty sure he said its alternator interference, so i'd be looking at options around that area

[Kusanagi]

There are a few reasons for this to happen.

(1) Grounding, this is caused by the ground difference (potential difference or a more common term ground loop) between the head unit and amp. Remedy: make sure the grounding of the amp and head unit are as short as possible, mount it to a clean chassis spot, preferably chassis with exposed bare metal.

(2) Crappy interconnects. Remedy: pay a few extra bucks to get better interconnects with strong shielding, I have had this alternator whine problem with cheap cable, but as soon as I tried with my 150 bucks cable problem is gone, you may still find cheaper cable with good 2-3 layer shielding. Remedy 2: try separate the interconnects from all power cables, ie, don't put them in the same wiring loom as power/ground), as far apart as possible. Remedy 3: try a ground loop isolator from Jaycar (may not work and sound quality will suffer a little), the ground loop isolator is to help isolate the ground between the head unit and amp which connected by the interconnect, same reason from (1). You can try this out, crank up the input gain on the amp with head unit hooked but no music, you will hear the whine, but as soon as you disconnect the interconnect, whine will be gone.

Hope that helps.

Ket

[crazyboosta]

13bwankel's on the right track. 90% of the time interference is caused by having power cable and RCA for amp running down same side. I would start by re routing the power cable for amp if you still get noise you can also buy noise suppressors that will plug into your RCA leads and kill the noise.

[13bwankel]

I can help you out with those if you've after some.

[sedgu]

I'd suggest you have the amp rca's running down the same side of the car as the fuel pump power cable (or amp power cable) try reversing the setup you currently have first.

Could also be your altinator... perhaps?

Yeah I had the amp power cable running down the same side as the RCA inputs like you said, just seperated them and it worked a treat! cheers for the help guys :D