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Discussion Starter #1
hello everyone, i recently purchased 01 from a friend. now when he purchased the car it already had aftermarket system installed. it always had alternator whine and static coming from front speakers. my friend never cared but now i own it and it's driving me crazy. there is a reputable shop near my work called abc electronics. my car was there 3 times alreday and they can't solve the problem. the whine and static are there even when the radio is off and it gets louder with rpm's.

car has: 2 rockford fosgate amps( one for the subs and one for mids and highs) , mb quart front and rear speakers, 2 x 12 inch eclipse subs. everything is still connected thru stock amplifier that works fine. abc guys tell me this is an older system but it was expensive when purchased and they say installation looks fine.
they tried everything ... filters, grounding everithing again, replacing one of the amps(for mids and highs) cause it had some bad connectors,changed the output converter , they also set gain on minimum on the amps....i am running out of patience and money....please give me any other suggestion on what to try....sorry for the long post
:1zhelp:
 

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So, I had a similar problem when I pulled everything from mine. But I replaced everything. I'm not using ANY stock components. We found that the head unit was the problem, even though it was brand new out of the box. We tried everything as well. Different amps, different grounds. The problem was the head unit.

Honestly, I'm very surprised that you're running an aftermarket amp through the stock amp... am I reading that right? I know that you'd do it for the built in cross overs. But you'd be better off getting another head unit to replace the nav, and eliminating the stock amplifier. That could very well be the problem you have.
 

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Discussion Starter #3
^ thanks for the reply. i don't really listen music on high volume. the system was already in the car when i bought it .i am not gonna invest more money in the music system. if i had all the stock components i would probably put them back in and throw this one out.
 

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That would probably be your best bet. You can remove the aftermarket amplifiers and subwoofer and leave it stock. Would probably eliminate the whine.
 

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hello everyone, i recently purchased 01 from a friend. now when he purchased the car it already had aftermarket system installed. it always had alternator whine and static coming from front speakers. my friend never cared but now i own it and it's driving me crazy. there is a reputable shop near my work called abc electronics. my car was there 3 times alreday and they can't solve the problem. the whine and static are there even when the radio is off and it gets louder with rpm's.

car has: 2 rockford fosgate amps( one for the subs and one for mids and highs) , mb quart front and rear speakers, 2 x 12 inch eclipse subs. everything is still connected thru stock amplifier that works fine. abc guys tell me this is an older system but it was expensive when purchased and they say installation looks fine.
they tried everything ... filters, grounding everithing again, replacing one of the amps(for mids and highs) cause it had some bad connectors,changed the output converter , they also set gain on minimum on the amps....i am running out of patience and money....please give me any other suggestion on what to try....sorry for the long post
:1zhelp:
I need more specifics on exactly what you have installed.

I'm guessing you have the stock amplifier with a Cleansweep to put the signal back together? If not, then I have no idea why you have the stock amp if you also have a sub and mid/high amp.

Alternator whine is caused by 2 things:
1. Ground loop
2. Noise in the power line.

#2 is extremely rare.

#1 is extremely common. And since you have aftermarket amps, I can guarantee they are not grounded at the same location as the rest of your electronics (bordmonitor, nav computer). Which means you have ground loop. I assume someone has already tried using ground loop isolators?

Post more info on your system and high res pics of everything and I'll give you some thoughts...

d-
 

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Get rip of the factory amp and get RCA's straight from the headunit. That will solve your problem if you are using the stock radio.
 

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A ground loop isolater might help reduce the whine, it might not. It did not in my case.

And besides, the system should not be running an aftermarket amplifier through the stock amplifier.

If you want to retain it to possibly return it to stock if you sell the car, that's fine. I still have all my electronics in place accept the head unit and aftermarket speakers. Returning it to stock is cake.

But really, at least remove the stock amp from the equation.
 

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Discussion Starter #9
thanks to everyone their suggestions. i wish i was more elctronically inclined so i can describe the system that i have a little better.i also have no clue why it still have stock amp. i am going to abc shop back on monday and i will ask about ground loop isolators and let them know about suggestions you guys gave me. the owner of the shop did suggest that it might be coming from my had unit but replacing it with an aftermarket one is out of the question. i don't have the original stock components because they never came with the car after i bought it and me buying them now used somewhere and paying for installation would be too expensive unless of course someone from chicago wants to trade me for their stock system and do the swap himself :). i would need guarantee though that the whine would be gone lol.

i will try to take some photos and post them if the weather permits.

thanks again guys for all the help, i will post what happened at the shop on monday
 

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A ground loop isolater might help reduce the whine, it might not. It did not in my case.

And besides, the system should not be running an aftermarket amplifier through the stock amplifier.

If you want to retain it to possibly return it to stock if you sell the car, that's fine. I still have all my electronics in place accept the head unit and aftermarket speakers. Returning it to stock is cake.

But really, at least remove the stock amp from the equation.
Alternator whine sucks to eliminate.

I agree with your statement about eliminating the stock amp, but it is only recently that doing so has become "normal". Most shops are happier using a Cleansweep, and hence my question.

As a side note, "returning to stock" after removing the amp is really a matter of finding some discontinued parts (good luck - I tried) and creating some customer enclosures (easy!). Otherwise, once the stock amp is out you need to cut connectors to splice into the factory speaker wiring.

d-
 

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Get rip of the factory amp and get RCA's straight from the headunit. That will solve your problem if you are using the stock radio.
Sadly, it will not. Doing so AND using the factory ground location for your aftermarket components should, however.

Anyone know where the factory ground location is? Me Neither :)

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Discussion Starter #13 (Edited)
^ so if they find that there are no ground loop isolators, how many do i need and where should they be installed? i was reading that you should put one between head unit and the amp ...would i do it in the dash board area behind the head unit or by the stock amp. in the trunk? where else should they be installed if more then one is needed ?

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^ so if they find that there are no ground loop isolators, how many do i need and where should they be installed? i was reading that you should put one between head unit and the amp ...would i do it in the dash board area behind the head unit or by the stock amp. in the trunk? where else should they be installed if more then one is needed ?

thank you
Hi hayabusa,

Ground Loop Isolators (GLI's) are used 1 per channel, and should be used between the first 2 components that do not share a grounding location.

As I think I mentioned before, without knowing your system, it is hard for me to tell you where this is. PICS PLEASE!

Based on your description, I would put the GLI's between the existing RCA cables and your aftermarket amplifier - this could be wrong, however, depending on your system.

Oh, and that thing everyone calls a headunit, isn't. It is a screen. The parts of the stereo that actually perform a headunits duties (tuning, CD, amplification) are located in the back left corner of your trunk.

d-
 

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Get rip of the factory amp and get RCA's straight from the headunit. That will solve your problem if you are using the stock radio.
The HU produces no music. Actual radio guts are in the trunk, where the amp is.

If the aftermarket amp is amping the stock DSP amp, kill the aftermarket amp. That is an incredibly lame setup and does nothing.

Ground loop isolater for $10 at Radio Shack should solve your problems (mains hum). If not, you'll have to ground at the same site as the item causing your whine, which, unfortunately, is in the engine area. The potential of your ground in the engine area by the magneto is different than in your trunk.
 

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The HU produces no music. Actual radio guts are in the trunk, where the amp is.

If the aftermarket amp is amping the stock DSP amp, kill the aftermarket amp. That is an incredibly lame setup and does nothing.

Ground loop isolater for $10 at Radio Shack should solve your problems (mains hum). If not, you'll have to ground at the same site as the item causing your whine, which, unfortunately, is in the engine area. The potential of your ground in the engine area by the magneto is different than in your trunk.
have you actually traced the wires from the trunk to the engine bay? If so, where exactly is it located? Where does the headunit ground join the harness from the trunk? For that matter, how does the harness get from the trunk to the headunit? I'd obviously like to move mine :)

d-
 

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Discussion Starter #17
i don't think this shop is gonna be able to help me out... i asked them if they tried ground loop isolators and they said they did with no success . they said they used 2 but after testing they say it didn't help static or the whine so they removed them. i was reading that all the aftermarket wires should not go on the right side of the car and that running them on that side could also cause alternator whine but i have no idea how my car is wired and the shop is saying it would take them 3 to 4 hrs to check...i think they are getting tired of me....problem is i dont know any other shop close to me that wouldn't require for me to drop the car for couple of days and that would know problems on bmw stereo systems and how to fix them...
 

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i don't think this shop is gonna be able to help me out... i asked them if they tried ground loop isolators and they said they did with no success . they said they used 2 but after testing they say it didn't help static or the whine so they removed them. i was reading that all the aftermarket wires should not go on the right side of the car and that running them on that side could also cause alternator whine but i have no idea how my car is wired and the shop is saying it would take them 3 to 4 hrs to check...i think they are getting tired of me....problem is i dont know any other shop close to me that wouldn't require for me to drop the car for couple of days and that would know problems on bmw stereo systems and how to fix them...
GLI's don't always solve the issue - I use them and still have alt whine, just not very much.

As for running wires on one side of the car or the other I wouldn't worry about it - your power wire (the only one that matters) is run on the right side of the car, but unless you have an aftermarket headunit all the rest of your stereo stuff is on the left.

Alt whine is very difficult to diagnose and harder to resolve. Anyone who tells you different probably doesn't know what they are doing. If you can't give up your car for a day or so then you are left with 2 options: live with it, or have the aftermarket stuff removed which will probably take a day or so...

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They likely didn't "rewire" anything from front to rear. It's too much of a hassle. Instead what they probably did was connect the aftermarket amp and ran it through the stock amp. This would allow the system to use the stock amp's crossovers so your sound is distributed to each speaker correctly. It would also mean that all the wiring remains where BMW intended it to be, and that's fine. The issue of the wiring being on the right or left or down the middle all depends on the car. If I remember correctly, speaker wire itself should not be picking up noise, only the RCA should be causing that.. IF it is in fact a line issue... which I highly doubt.

In fact, even my own "100%" aftermarket system still uses factory speaker wire. It's a simple matter to tap (without cutting) the existing wire from the bundle that goes into the stock amp, and connect correctly in the doors/rear window.

Really, the best bet is to remove the aftermarket amp. You can still use the stock amp and aftermarket speakers obviously - and it shouldn't be difficult at all to do.
 

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have you actually traced the wires from the trunk to the engine bay? If so, where exactly is it located? Where does the headunit ground join the harness from the trunk? For that matter, how does the harness get from the trunk to the headunit? I'd obviously like to move mine :)

d-
There is a ground pin in the trunk, but requires gutting everything on the left side. I'm uncertain if the HU grounds in the same spot. I traced the cable assy from the trunk, under the seat on the left side, under the door panel stop....then it magically appears at the head unit. :thumbsup:
 
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