No Amp + Aftermarket Speakers=Crap

[Seanz0rz]

all power wires should be PERPENDICULAR to any signal wires from the head unit to the amp, now this is impossible. somethings you can do is wrap the signal wire with aluminum foil, and separate the signal wires from the power wire where ever possible.

for example, on mine, i ran power down the left side and signal down the right, and where they meet up i tried to cross them perpendicularly,

also, does the whine change with increased throttle? if so thats alternator whine, you may also have a ground loop problem. are all the grounds going to the same spot, and are they well grounded?

have a looksee here:
http://www.mp3car.com/vbulletin/car-...ing-guide.html

[traben27]

all power wires should be PERPENDICULAR to any signal wires from the head unit to the amp, now this is impossible. somethings you can do is wrap the signal wire with aluminum foil, and separate the signal wires from the power wire where ever possible.

for example, on mine, i ran power down the left side and signal down the right, and where they meet up i tried to cross them perpendicularly,

also, does the whine change with increased throttle? if so thats alternator whine, you may also have a ground loop problem. are all the grounds going to the same spot, and are they well grounded?

have a looksee here:
http://www.mp3car.com/vbulletin/car-...ing-guide.html

Thanks...that's my problem right there. I'll have to fix it tomorrow or something. It does also do the alternator whine, so I just need to check the ground on the amp, or is there anything else that would be wrong?

[Seanz0rz]

check the grounds, and see if moving the wiring around changes the noise.

[traben27]

Well, I looked at the amp ground and it wasn't the best so I fixed that and that cured the noise that was affected by the engine. But I still have the high pitched humming noise through the speakers only when the car is running. If i unplug the front speakers (via the rca cables at the amp) the noise goes away but of course so does the sound from the front. It does the same for the other way around as well...any ideas?

[Seanz0rz]

does the sound change (pitch or volume) as RPMs change? if they do then that is alternator noise, you need to separate the signal cables(rca cables, not speaker cables, speaker cables are not harmed by power signals) from power cables. ill try to snap some pics of my mess of wires.

ok here are pics, they are dark, sorry




you can see everywhere the foil crosses the power cables (gigantic red wire), they are perpendicular. the small red and black wires are speaker wire, and those are unaffected. i wrapped the signal wire (the RCA from the deck to the amps) with foil. doing both those things solved my problem.

[Seanz0rz]

yea when i did the install, i actually only had about a dollar in my pocket, and was borrowing gas money from friends for a while there, so it was a free fix.

[traben27]

I'll try to do that but I actually rerouted the power cable to go between the center console and the seat, while everything else is along the trim at the edge of the carpet by the door. The closest it ever comes to the RCA cables is right under the steering wheel and it's probably 3 or 4 inches away (I think?) Could this possibly be a grounding issue? It doesn't change with the rev of the engine, just the fact that the engine is on is what makes it come on.

[Seanz0rz]

if it does not change with the engine revs, then it is not alternator whine. it is most likely a grounding issue.

[traben27]

I'm slightly confused by your response, previous posts seem to say that alternator whine is caused by bad grounds, if I don't have alternator whine, then how is it most likely a bad ground? Maybe I'm just misreading previous posts...

[Seanz0rz]

ive always understood alternator whine as just interference with the signal wires coming from the alternator(through the power wire), while a grounding problem or ground loop being different potentials (voltages) in the grounding plane that harm the signal.

im not great at explaining this, basically all your grounds should be at one spot, the grounding point should be well sanded to expose bare metal. use appropriately sized conductors.