engine noise through speakers

[tac0meat]

i have a 91 eddie bauer and i just put in a panasonic day/night glow head unit, all pioneer speakers power by an american pro 2ch amp(im upgrading soon) a kenwood 12 powered by a jensen amp. but my problem is that i here a faint whine in tunt with the engine speed through the pioneersin my doors, i also hear a popping noise in tune with the engine and a popping noise while my blinker flashes. i think the whine is caused by the altenator but i dont know where all the popping comes from and how do i stop all those noises?? btw i only hear them at low volumes.
thanx in advance

 

[JTang]

Hi Austin,

There are a few probable causes for the problem. In most to least likely, they are:

1. Most engine whine is caused by ground loop noise. Try grounding your amps to a different area. This is the MOST likely problem, because of the fact that you hear the pops. Make sure when you ground the amps, that the wire is no longer than 1.5 feet at VERY most, two feet. Try to ground your amps at the same point, and where you ground it, also, scrape away any paint so it's a metal to metal contact.

2. EMI (Electromagnetic Interference) can also be from large power sources affecting the sound signal. Make sure your RCA cables are away from power sources and your amplifier power wires. This is the second most likely, because you hear whining in tune with the engine's speed, due to the alternator. You don't hear the whine when the car is off, do you?

3. Your American Pro amplifier has poorer EMI filtering, and when you get the upgrade, it will probably help. This is the least likely solution.

The other solution is to get a noise filter for a few bucks, they help a bit, but it's more a band-aid than an actual fix, and finding the solution to either problem 1 or 2 will help you out more by actually fixing the problem.

Hope this helps you a bit.

 

[tac0meat]

thanks for the help Jtang.
i think that my problem is in the american pro amp because i only hear the noises through speakers powered by that amp. i ought to have a new 4ch amp in a week or two (probably a power acoustik) but i will also check over my rca cables tommorrow and make sure that they are not too close to the power wires. by the way how close is too close to the power wires? about a foot or so of distance ought to be enough right?
thanks again for the help

 

[JTang]

I guess one foot at a minimum. The usual standard, however is to run the power wires down one side of the car, and the RCA's down the other. Just to be sure if it is the American Pro amp, I guess you could just try switching your speaker wires to the other amp and see if you get the same noise, as long as you don't blow the speakers of something by applying too much power. There may be a chance that the other amp is getting the whine too, but you just can't hear it because the subwoofer won't play that high pitched of a sound. Try swapping your existing amps or something and see what you come up with. Make sure to always connect the RCA's *after* you connect the power wires.

Good luck!