Need a little help here.....I just installed an amp in my '94 Teg. It sounds great, but whenever I rev the engine, I can hear a high pitched whine coming from the speakers that matches the revs. I can hear it the most when I turn the volume all of the way down. Isn't this caused by a grounding loop (ground issue)? Any advice on how to fix it?
Any and All help is greatly appreciated.. Thanks

 

what it most likely is,
your power wires for the amp and the signal wires are probably too close together, did u run the power/remote and signal wires on opposite sides of the vehicle? if not, thats whats wrong

 

Ground loops are when an unintended connection to ground is made resulting in more than one path to electrical ground.

Keep your signal and power wires at least 18", Ensure that your amp has a good solid ground and the chasis of the amp does not touch bare metal. Also, if the RCA has a small thin wire in it, make sure you are gounding this wire at both ends and not connected it to remote 12v like most installers do.

If you still have noise, come back and we can go further. Also, what kind of rca's are you using (you don't require super expensive..but these do help as well)

-Rage

 

I sure as hell did!
I should have known better, but I guess it never dawned on me to get that power lead as far away as possible.
I'll rewire it tonight and see if that helps.
Thanks Guys...


[Modified by GSR-REX, 10:00 AM 9/5/2002]

 

Thanks for the help Rage...
Man, that hum is still there! I realized that I had put the power lead alongside the speaker wires so I rewired it last night to get it away from them. But it still hums with the revs of the engine. I even went as far as to run the power lead on the OUTSIDE of the car just to make sure it wasn't interfering with the speakers...still no good.

I also redid the ground wire. I had previously just drilled a hole in the body just under the rear passenger speaker. I took my dremmel and made sure there was no paint around it and then attached it with a screw and washer. last night I took that off, crimped a wire connector on the end of the wire and attached it to the same spot as the ABS ground...still no good.

What should I do now? I was thinking about running a ground wire straight to the negative terminal on the battery. Will this work? It won't damage anything will it?
PLS help...I'm going crazy over this.
TIA


[Modified by GSR-REX, 10:01 AM 9/5/2002]

 

nono, you DEFINETLY want the shortest ground, running to the ground terminal of the battery will do nothing for you.

did you check the radio and rca (not amp) grounds like I asked? Make sure your deck is properly grounded, and the rca if it has a wire for it (a thin one along the middle) is grounded.

if that STILL doesn't work...What kind of rca's do you have?

http://cgi.ebay.com/ws/eBayISAPI.dll...tem=1377478379

for 2 chan

http://cgi.ebay.com/ws/eBayISAPI.dll...tem=1377478460

for 4 chan (prob what u want)

this is the cable i love to use they are twisted pair and offer good noise protection.
you can prob pick it up at best buy or circuit city (only us CANADIANS need to buy off ebay..grr..)

-Rage

 

Yeah, I checked my RCA's...they don't have a ground wire built onto them.
I never messed with the radio's ground..I just left it intact on the OEM wiring harness.

I just have normal gold plated RCA's. I figured that they would be okay since I've used this kind before in similar setups for friends, but they didn't have these problems.

Also...on my 4-channel Line output converter box that i connected to the stereo, it had a ground wire coming from it that I grounded on the stereo chassis (there was already a place there where something else was grounded, so I just used that.

I had read that you should try to stay away from grounding in two seperate spots...so I thought that was it. So, I took that one off, but it actually got worse! Before, it was just a dentist-drill type whine, now there's a low fast-clicking sound at low rpms and then turns into the whine at high rpms

Thanks again for any help....any more suggestions?



[Modified by GSR-REX, 11:55 AM 9/5/2002]

 

What kind of amp do you have, is it brand new, and where is it mounted? If it is screwed down to metal you may want to isolate it by placing a piece of wood under and screwing into that. Good luck.

 

Its a JBL 4-channel amp putting out 50watts RMS/channel. The model is LCA504.

Yeah...I checked that too already.
Thanks

 

Still out there Rage? I sure could use a suggestion or two.
Thanks...

 

how are you inputs gains set...are they wide open or are they set approx half way....check them out...these are like flood gates they allow the amp to use what signal is available. If they are wide open the allow all types of unusal things to happen such as noise. There are a few steps involved in elinating "mice".

 

IT'S FIXED...NO MORE NOISE

Wow Evil Teken...ya laid down the knowledge on me, didn't ya? I sure as hell appreciate all of the help everybody.

Here's what I did when I got home last night:

I went back through the entire setup from headunit to amp to speaker. The ground wire on my line output converter had previously been attached to a grounding point I found on the chassis supporting the stereo. In my troubleshooting, I had disconnected that wire thinking that I shouldn't have grounded the system in two different spots. When I took it off, the whine actually got worse!

So, I took that wire and spliced it into the ground coming from the radio. Then I took out the power lead, sheathed it in its own cable tube and ran it down the passenger side of the vehicle.

Then, I rerouted the remote lead from the power antenna so that it wasn't near any other wires. Finally, I took off the engine ground cable ( Evil Teken)..cleaned it up real good with steel wool and made sure it had good contact to the chassis...then put it back on.

I tested it and the whine was gone! I tested it 4 more times as I progressed through the stages of putting the interior back together. it never came back.

I have been whine free now for about 18 hours now and it feels great!

I just want to seriously thank everybody that offered their help. Especially Rage and Evil Teken. I absolutely appreciate it

Happy Friday.....the e-beer's on me this morning!

 

wicked!

-Rage