First off, i wanna say these forums rock! I have spent nights just reading through all the information posted in here, so keep up the great work.

I am pretty sure i have read about this already at one point, but can't find the post.

Last week i wired up my subs and amps, and they sound and hit great. Only problem is, whenever i use any other electronic equipment in my car, i hear a somewhat of a bumping sound through the subs. For instance, if i hit the brake petal, the subs hit. Here's my current setup.

Before i read up on my car at this site, i figured like all my previous cars that the battery was in the hood, so i already ran a 4 gauge power cable from the hood, through the firewall back to the trunk (which i am going to rip out since the battery is in the trunk... duh!). Then i used the line converter to tap into the rear speakers for the rca connectors for my amps. In my '93 dodge shadow that noise was caused by crappy rca cables being ran next to the power lines, so after an upgrade in rca lines, that problem was resolved. However i figured since the rca cables never leave the trunk, that wouldn't be a problem. Hopefully this info helps you all tell me what stupid mistake i made.

I guess the noise that is being produced is possibliy from poor grounds?

any help is greatly appreciated!

 

most likely grounds, get a ground loop isolator, should remove the noise, first time i hooked up my stereo, i had humming from the fuel-pump....... sweet to listen too, not,

 

sounds like your getting feedback, there are many possiblitys for this, ground, amp"cross-overs" voltage, maybe radiated noise through the RCAs

 

well i got a great ground where the wire from the negative terminal of the battery is bolted to the car, and i purchased a ground loop isolator, same thing. I wouldn't think its the rca cables since there is nothing even within 6 inches of the rca cables, i have them wired tied together to keep any power cables from coming in contact with them? am i missing anything?

I wouldn't think this would change anything, but i have a 4 gauge wire coming from positive on battery to a distro. block, with 2 8 gauge wires branching off from there. At the time, i am only wiring up one sub and amp to help find the problem.

 

Any suggestions? Would the next step be replacing the rca cables?

 

how many rca wires do you have and how are they tied together? also are you sure its not run on the same side as the alt- bat wire?

 

Thanks for the response man.

I have two pairs of rca cables, but i'm only going to wire the one up for now to help figure out where the noise is coming from. The lineout converter hookup is in the trunk obvsiously so the rca cables never touch or come within 6 inches of and power/ground wiring. I just simply have a few zip ties to keep the rca cables bundled up with each. Each pair of rca cables are bundled seperately.

 

also if you have an 07 balt its alot different my harness cost me 200 bucks beaucse of the LAN system

 

What wiring harness are you referring to? I didn't do any work behind the dash with the factory h/u, i just branched off the wiring to the rear speakers. Is there something that i missed?

Here's a link for a wiring picture as far as the power and ground. Click on the image to get a bigger view.

http://tribalfiles.net/PhotoGallery/...&cat=0&pos=-13

 

I guess my questin is what is the "noise" you hear? Is it only the thump when you hit the brake or is it actual engine noise that varies with the rpm's of the cars alternator? I do wanna know where you hooked remote turn on into the vehicle. If you used the fuse box, thats very "noisy" and possibly will give a power surge through other circuits when one circuit pulls power. That will give you your thump noise when you hit the brakes. Just curious.

 

It's not engine noise, just when i hit the brake pedal, or use the power window buttons, things of that nature, i don't hear like an alternator wine or engine wine, etc.

I never thought of that tho, because it is wired to the sunroof fuse as suggested by someone here on the forum. So if that is the problem, do you have another suggestion of what line to tap into for the remote on.

 

well the sunroof fuse works... but honestly the best place to get the remote is from the hu but since that is impossible with oem hu that fuse should do... it shouldnt cause that much noise problems. IM sorta stumped with this one. you said your only using one set of RCA's right? What brand are the rcas? Myabe you need a better quality rca. My first instinct was that if you ran 2 rcas together it may cause some noise and a 4 chan rca is always better then running 2 together

 

I am stumped as well. I ran the remote on wire straight to the battery to see if the noise was reduced but the same result...

So the problem has to be somewhere between the rca inputs on my amp, and my connection to the line out converter to the rear deck speakers..

I'm going to run out tomorrow morning and pick up some new rca cables to see if that helps at all. Any specific brand you think i should pick up?

If this doesn't work, I'm out of ideas... Is it possible that the line out converter is causing the problem?

 

actually it is possible... but i have an extra one at my house if you wanted to pay shipping ill let you have it.

In terms of rca brands just get something reputable.. Rockford, JL, Knu Konceptz are the top 3 id recommend but theres also stinger kicker ect ect just dont get wallmart type stuff

 

Well, i'll pick up the new rca's and go from there,, Haha, if i was using wal-mart equipment, and was complaining about problems, i would let you shoot me in the head.

In the meantime, im gonna run down to my car, and get the brand and model number of the converter i'm using, and see if google can give me any complaints about it. Now that i think about it, the converter did have 2 internal dials you could turn, but i am not sure what they adjusted?

Thanks again for your responses

 

I got the same problem HELP me please
When engine is off there is no noise but when i start it the noise begin

 

Emperor, here is the converter i purchased.

http://www.installedge.com/products/...productID=1108

Only difference is mine is a 2-60 watts. I don't know if this brand jumps out as being walmart quality material or not, like i said it was the only one available at circuit city at the time. If you think it could make a difference, i would be more than happy to take you up on your offer. Let me know what you think when you get a minute.

Also, since i tapped into the rear speakers, would you recommend hitting the rear speaker connection before it gets to the factory amp? So tapping into the input side of the amp instead?

 

nah it shouldnt matter before or after.... and the install edge is made by rf same thing that i got and hasnt failed me yet. Only thing is mine isnt adjustable direct plug and play. im thinking thats where your problem might be. have your tried messing with the knobs on it while the car is on and the radio is on but at 0 volume (so all you would hear is noise)

http://www.installedge.com/products/...productID=1106
thats the one that i have and while it does say adjustable the knobs arent there so its not adjustable and it worked very well in my moms car until i yanked my system out and put it in mine (my dad got all hurt)

i honestly think its the knobs but if you wanted to try it a ground loop isolator might help... usually ive only herd of using them on cases where there is engine whine alt whine ect but it may be worth a shot. Honestly at this point i would mess with the knobs some to see if you can clear it up and if not take it to a shop to do a quick look at it. Im thinking it needs to be "tuned" with a multimeter

 

Yah, i adjusted those dials in the very beginning but it just seemed to adjust the loudness of the subs, unless i was mistaken, i'll check that out once i get the new rca's.

 

Ok but I have something to tell you about the wire of the rear speaker I got the wiring diagram from gm and it says:

Left Rear +.........Black or Brown
Left Rear -..........Yellow

Right Rear +........Dark Bleu
Right Rear -.........Light Bleu

So that will other guys that whant to know

 

ever get it figured out?

 

No, still haven't figured out whats going on, gonna run a few more tests this weekend.

For the meantime, i just had to turn the amps down really far so that the noise isn't as noticable, (gain, freq. etc,.).

I have a few more ideas on what could be causing it so i'm gonna do a little more trouble shooting. I'll definitely let you know the results.

 

Try grounding to a different location...make sure it is clean. Is there a power antenna wire off the radio? (dunno,I have an aftermarket head unit). If there is, that is used for the remote turn on. After that, start disconnecting and/or bypassing components to see if the noise goes away...one at a time. I have never needed isolators ar anything for any of my systems.

 

The Problem with using a power antenna wire is he will only get amp turn on when the radio (AM/FM) is on.

I'm an installer at Best Buy here in ct, and if it was my car I would:

1. Grab remote turn on at the ignition/accessory wire up front.
2. Try a better ground
3. Change the Line Output Converter for a new one
4. From what I have heard our power systems surge something awful, seems to be the case with some guys aeroforce interceptor units acting up. Try throwing a small capacitor (1 farad) on the powerline, should level out any voltage drop
5. If all that fails.... God only knows...

 

Well this is a very late update/post, but i finally got rid of that annoying sound... Between a new line output converter, and putting a capacitor in my system, the sound dissapeared! Thanks for your help folks!