the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
icon

Ground Q/A sticky


Post ReplyPost New Topic
< Prev Topic Next Topic >
forbidden 
Platinum - Posts: 5,378
Platinum spaceThis member has made a donation to the12volt.com. Click here for more info.spaceThis member has been recognized as an authority in Mobile Audio and Video. Click here for more info.spacespace
Joined: November 01, 2003
Location: Alberta, Canada
Posted: August 19, 2004 at 6:12 PM / IP Logged  
Post your questions related to ground / noise issues here. Industry professionals and educated users will reply to these types of topics here. This will greatly reduce the amount of searching done and the repititous questions as well. It will help greatly to post the make / model of all of your equipment as well as the vehicle it is in. Post what you have tried and the results as well. A lot of noise issues are a process of elimination that when one reads what you have done, that may solve their problem.
Top Secret, I can tell you but then my wife will kill me.
xavierny25 
Member - Posts: 24
Member spacespace
Joined: July 28, 2004
Location: United States
Posted: August 19, 2004 at 6:20 PM / IP Logged  

question, is it ok to ground 3 amps (all 8 gauge all 2 feet long)to a distrabution block and ground it with 4 gauge also at 2 feet?i have 2 kickers 250.2 and a 350.2 and last but not least a sony mono amp at 800 wattts.

forbidden 
Platinum - Posts: 5,378
Platinum spaceThis member has made a donation to the12volt.com. Click here for more info.spaceThis member has been recognized as an authority in Mobile Audio and Video. Click here for more info.spacespace
Joined: November 01, 2003
Location: Alberta, Canada
Posted: August 19, 2004 at 6:25 PM / IP Logged  

Yes this is fine to do. I will leave out the particulars on grounding for now. If you have specific questions or problems that arise post them up and they will be answered. Once we have compiled the info for the main grounding topic, go through your system again and address the issues that may be specific to your installation.

Top Secret, I can tell you but then my wife will kill me.
TubeDriveRMD 
Member - Posts: 8
Member spacespace
Joined: August 18, 2004
Location: United States
Posted: August 20, 2004 at 9:28 PM / IP Logged  

Hi guys. I recently had my system professionally installed. Cosmetically they did a great job. Unfortunately, i have an awful alternator whine.  I have only had the system running for 1 wk yet i cant stand to listen to it because of the noise!!! aaaaaaggggggggghhhhh!

Anyway, i did a few tests. im fairly certain (please speak up if im off base) that the ground loop is entering via the HU ground which is grounded up front through the original factory ground.  Im assuming this is through the wiring harness?? anyway ive isolated it to the HU ground because......

 1. I replaced the head unit (sony cdx c910) with new eclipse cd8443.  ground loop persists

 2. I patched my ipod into the eclipse via the AUX input.  same ground loop.

 3. i disconnected the eclipse rca output and directly patched my ipod into my line driver. The line driver normally takes the output of the HU via 18 inch RCA cable and converts it to balanced XLR outputs whihc is routed to the back into xover, amps, etc. After patching in my ipod (headphone out) , Viola! the alternator whine disappeared.

Am i correct in believing the HU ground is the cause of the ground loop.  The remainder of the system is grounded in the back (3 amps, xover, etc).  I know install rule 101 says to ground all compnents to a SINGLE spot.  I am assuming that this includes the HU. Nevertheless, i am extremely disappointed in my installer.   1000$ install and i have alternator whine??? 

So, i rescheduled to have the installer go back and run a ground cable from the HU to the back where the ground distribution block is located. 

So what do ya'll think??    I am well aware that car audio is frought with noise but i feel they should at least ground the system properly .  Did they follow standard install technique and i am being too demanding???   Is my HU ground the reason for the loop? Thank you for your input.

Btw, car = 1997 civic

Eclipse cd8443
Phaze LD1 line driver
Phaze LDX-23 Xover
Butler1500 TubeDriver (2)
Dynaudio 220
Boston Pro 10.4LF
Zu Cable balanced XLR cables
Kimber Kable speaker wire
forbidden 
Platinum - Posts: 5,378
Platinum spaceThis member has made a donation to the12volt.com. Click here for more info.spaceThis member has been recognized as an authority in Mobile Audio and Video. Click here for more info.spacespace
Joined: November 01, 2003
Location: Alberta, Canada
Posted: August 20, 2004 at 9:37 PM / IP Logged  
As I am still at work and currently having trouble installing ((happens when you try and cut off your finger by accident - oops) also makes typing difficult), I'll answer some of this until my next install shows up. Have you tried to bypass the line driver yet? Plug the rca outputs of the Eclipse direct into the amplifiers. Did the installer check the ground return resistance? Have muting plugs been tried? Install is here, gotta go, If I have time I'll post back later or maybe one of the guys will answer.
Top Secret, I can tell you but then my wife will kill me.
TubeDriveRMD 
Member - Posts: 8
Member spacespace
Joined: August 18, 2004
Location: United States
Posted: August 20, 2004 at 10:54 PM / IP Logged  

hi rob! thanks for your help.!

yes, i have bypassed the line driver and the whine persisted.  also, the gains on the line driver and amplifiers are minimized.  i bypassed the line driver by plugging rca's directly from HU into xover. 

i could use the HU's xover and bypass the line driver and tube xover and patch an rca cable directly from the HU to amp, but havent pursued once noise disappeared swapping eclipse source for ipod soucre. i know the ipod is not part of the car's electrical circuit obviously, but the line driver, xover, and amps are connected to the electrical system; so am i wrong in assuming that they are not the source of the loop. since i 'removed' the HU from the signal chain, isnt this the culprit???

no, the installer did not check ground resistance.

Eclipse cd8443
Phaze LD1 line driver
Phaze LDX-23 Xover
Butler1500 TubeDriver (2)
Dynaudio 220
Boston Pro 10.4LF
Zu Cable balanced XLR cables
Kimber Kable speaker wire
auex 
Platinum - Posts: 5,082
Platinum spaceThis member has made a donation to the12volt.com. Click here for more info.spacespace
Joined: December 23, 2002
Location: Arizona, United States
Posted: August 20, 2004 at 11:25 PM / IP Logged  
Perhaps someone could do a write up on how to make muting plugs.
Certified Security Specialist
Always check info with a digital multimeter.
I promise to be good.
Tell Darwin I sent you.
I've been sick lately, sorry I won't be on much.
forbidden 
Platinum - Posts: 5,378
Platinum spaceThis member has made a donation to the12volt.com. Click here for more info.spaceThis member has been recognized as an authority in Mobile Audio and Video. Click here for more info.spacespace
Joined: November 01, 2003
Location: Alberta, Canada
Posted: August 21, 2004 at 12:24 AM / IP Logged  
Bypass the crossover and the line driver and go direct from cd to amplifiers. Does the noise still persist?
Top Secret, I can tell you but then my wife will kill me.
auex 
Platinum - Posts: 5,082
Platinum spaceThis member has made a donation to the12volt.com. Click here for more info.spacespace
Joined: December 23, 2002
Location: Arizona, United States
Posted: August 21, 2004 at 1:30 AM / IP Logged  
I agree, you have alot of equiptment inline of the audio path.
Certified Security Specialist
Always check info with a digital multimeter.
I promise to be good.
Tell Darwin I sent you.
I've been sick lately, sorry I won't be on much.
flynntech 
Copper - Posts: 276
Copper spacespace
Joined: April 15, 2004
Location: United States
Posted: August 21, 2004 at 8:04 AM / IP Logged  

This is just my opinion so don't take it for gospel, running a ground wire all the way to the back is impractiacal. The only thing that makes any sense here is that all grounds should be at the same potential, zero volts.

Yes, the factory wiring is rarely in any kind of shape to supply clean power to the HU, this is common.  Ground the HU to the body right about where the HU is, if you have to run a ground directly to the firewall or floor, that's fine. Also, bring 12 + directly from the battery, fused as always.

A muting plug is simply an RCA plug with the two conductors shorted together. Anyone can do this with a pig tail, by splicing the wiring with a crimp. Soldering the pins together is better.

Just remember: DO NOT CONNECT THE MUTING PLUGS TO THE OUTPUT!!! 

The only purpose of the muting plug is to zero the input signal at the line level INPUTS......It will short the output stages of the HU or whatever else, since it is indeed a shorted plug.

Page of 24

  Printable version Printable version Post ReplyPost New Topic
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

  •  
Search the12volt.com
Follow the12volt.com Follow the12volt.com on Facebook
Saturday, May 27, 2017 • Copyright © 1999-2017 the12volt.com Donate to the12volt.com Advertising Top of Page
Disclaimer: *All information on this site ( the12volt.com ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
Donate to the12volt.com
Top
the12volt.com spacer
the12volt.com spacer