Alternator whine again, ground directly to battery.

[DR BOOST]

I CHALLENGE ANYONE.. that with three fine tuning instruments of my choice i can eliminate any noise from a car including alternator whine,exhaust noise, bad tensioner, squeeling belts , baby momma drama ,etc for ONE BILLION DOLLARS (in U.S. funds, all fifty dollar bills, no coins)... but this will be in the car of my choice, paid by you and title transferred to me. car must be delivered to Alaska and driven to China. I have a complex algorithim embedded in my brain carefully hidden in the OLD SCHOOL RAP section of my mind( carefully nestled between the sugar hill gang and Curtis Blow). I will accept anyones challege as long as this and all of my other criteria whether expressed or not are met. i must also ask my mommys permission too.

and in the end it was an RCA cord. Goodness Gracious

 

[A2000RICH]

I CHALLENGE ANYONE.. that with three fine tuning instruments of my choice i can eliminate any noise from a car including alternator whine,exhaust noise, bad tensioner, squeeling belts , baby momma drama ,etc for ONE BILLION DOLLARS (in U.S. funds, all fifty dollar bills, no coins)... but this will be in the car of my choice, paid by you and title transferred to me. car must be delivered to Alaska and driven to China. I have a complex algorithim embedded in my brain carefully hidden in the OLD SCHOOL RAP section of my mind( carefully nestled between the sugar hill gang and Curtis Blow). I will accept anyones challege as long as this and all of my other criteria whether expressed or not are met. i must also ask my mommys permission too.

and in the end it was an RCA cord. Goodness Gracious

no it wasn't a defective RCA cord...................RC

 

[DR BOOST]

no it wasn't a defective RCA cord...................RC

im just playing Rich. You are a highly respected expert in my books.

i was always intrigued by the 12 inch midbass on the gn. could you please share some more detailed pics of the gn as opposed to the ones commonly seen on the net.

 

[ITSAV6]

??????????

I used one new RCA cable, and one existing RCA cable. I ran the power/ground from the trunk to first check the integrity of the head unit and amps. Once we knew there was no whine, then we knew the head unit and amps were operating correctly. This was done with a short RCA cable and short power/remote/memory/ground wires. At the start of the test, we didn't know where the whine was coming from, although I guess a good bet would be from the front half of the car. Then I installed long wires but kept them hooked up in the trunk. I moved the head unit up to the center console, still no whine. Also at this point, the RCA cable running down the driver's side was not hooked up. I'm hoping I can use the factory black ground wire, ignition power wire (red), the green wire, and the orange wire in the dash for the memory. I'll experiment over the next couple of days and will report back.

Do you think the driver side rca is picking up the noise? Have you hooked up just the driver side rca?

 

[GNRick]

Do you think the driver side rca is picking up the noise? Have you hooked up just the driver side rca?

Richard said it is a big no no to run RCA's down both sides of the car. He said he runs them down the passenger side because it is easier to get them up to the radio that way. So I guess just pick one side and go with it.

 

[A2000RICH]

Do you think the driver side rca is picking up the noise? Have you hooked up just the driver side rca?

in almost all cases testing one side at a time will always lead to a misdiagnosis since the noise will usually be worse with BOTH sides connected and either side alone will usually appear quieter------------

let me give an abbreviated explanation of how a signal conductor usually picks up alternator wine------if you are familiar with a transformer you know a few basic things-----current flows through the primary winding and creates a magnetic field in the core-----this magnetic field in turn causes a current in the secondary winding since it also is looped around the magnetic core------the way alternator whine is injected into a signal conductor of a car is exactly the same way-------in a car we don't have a primary winding but we do have current flowing through the conductive chassis/body of the car because all of the electrical components in the car use the chassis as a negative conductor------this flow of current creates a magnetic field within the confines of the car-------any wire that forms a loop within this area will have a current induced into it-----a loop would be defined as a any part of a complete circuit run between two components-----any wire run through this area will have noise if current is flowing in the chassis-------its impossible for it not to have noise-----the goal in a scientific install is to minimize the "loop area" so the noise is below audible levels-----in any system installed in a car with enough gain applied or sensitive enough test equipment there WILL BE NOISE IF CURRENT IS FLOWING IN THE CHASSIS------the larger the loop the more the current and the more loops the more the voltage----------a single RCA run through the car will pick up very little of this noise because the loop area is minimal but it does exist--------a stereo pair of "RCA" will have even more loop area------a comolded pair will have less loop area than a seperate pair of wires------smaller wires will have less loop area than larger wires--------big fat "triple shielded" wires are the worst for noise---------when a pair is run down one side of the car and another pair is run down the other side it is an invitation for disaster since the loop area between opposite sides of the car is gigantic------the best course of action is to keep both pairs of conductors together as close as possible (taping or using loom) so the loop area of the 4 conductors is as small as possible--------of course it varies from car to car depending on actual current paths in the chassis, actual amount of current, vicinity of the wire to the chassis and other factors------BUT the most important thing to understand about this VERY COMMON type of noise is that shielding is TOTALLY ineffective to reduce it---------thats why in the toughest autosound noise cases the quietest wire is extremely small UTP (unshielded twisted pair) as long as there isn't a source of electrostatic noise (such as sparkplug or switching transients) that can only be stopped by shielding----------home stereos don't have this problem since homes are usually made of non conductive wood and we run neutral return conductors for the electric loads-------in homes we have to worry about the actual transformer cores in the individual components, light dimmers etc..........................RC

 

[GNRick]

in almost all cases testing one side at a time will always lead to a misdiagnosis since the noise will usually be worse with BOTH sides connected and either side alone will usually appear quieter------------

Just to clarify- Assuming radio is still in dash, and rca wires are run down both sides of car....if you disconnect the driver side cable at the amp in the trunk, would there still be the loop because the signal is still going down the wire? Alternatively, if you disconnect the rca wire at the radio, would this eliminate the loop? (I simplified it and assumed the factory wires in the dash are ok). I hope this question doesn't sound too dumb.

 

[A2000RICH]

Just to clarify- Assuming radio is still in dash, and rca wires are run down both sides of car....if you disconnect the driver side cable at the amp in the trunk, would there still be the loop because the signal is still going down the wire? Alternatively, if you disconnect the rca wire at the radio, would this eliminate the loop? (I simplified it and assumed the factory wires in the dash are ok). I hope this question doesn't sound too dumb.

that creates a condition altogether different-------there is still a loop between the L/R and +/- conductors of the stereo pair wire that is still connected------ the wire disconnected from the amp and still connected to the radio can still pick up noise that may be routed down the other side since they are common at the radio..............RC

 

[ITSAV6]

in almost all cases testing one side at a time will always lead to a misdiagnosis since the noise will usually be worse with BOTH sides connected and either side alone will usually appear quieter------------

let me give an abbreviated explanation of how a signal conductor usually picks up alternator wine------if you are familiar with a transformer you know a few basic things-----current flows through the primary winding and creates a magnetic field in the core-----this magnetic field in turn causes a current in the secondary winding since it also is looped around the magnetic core------the way alternator whine is injected into a signal conductor of a car is exactly the same way-------in a car we don't have a primary winding but we do have current flowing through the conductive chassis/body of the car because all of the electrical components in the car use the chassis as a negative conductor------this flow of current creates a magnetic field within the confines of the car-------any wire that forms a loop within this area will have a current induced into it-----a loop would be defined as a any part of a complete circuit run between two components-----any wire run through this area will have noise if current is flowing in the chassis-------its impossible for it not to have noise-----the goal in a scientific install is to minimize the "loop area" so the noise is below audible levels-----in any system installed in a car with enough gain applied or sensitive enough test equipment there WILL BE NOISE IF CURRENT IS FLOWING IN THE CHASSIS------the larger the loop the more the current and the more loops the more the voltage----------a single RCA run through the car will pick up very little of this noise because the loop area is minimal but it does exist--------a stereo pair of "RCA" will have even more loop area------a comolded pair will have less loop area than a seperate pair of wires------smaller wires will have less loop area than larger wires--------big fat "triple shielded" wires are the worst for noise---------when a pair is run down one side of the car and another pair is run down the other side it is an invitation for disaster since the loop area between opposite sides of the car is gigantic------the best course of action is to keep both pairs of conductors together as close as possible (taping or using loom) so the loop area of the 4 conductors is as small as possible--------of course it varies from car to car depending on actual current paths in the chassis, actual amount of current, vicinity of the wire to the chassis and other factors------BUT the most important thing to understand about this VERY COMMON type of noise is that shielding is TOTALLY ineffective to reduce it---------thats why in the toughest autosound noise cases the quietest wire is extremely small UTP (unshielded twisted pair) as long as there isn't a source of electrostatic noise (such as sparkplug or switching transients) that can only be stopped by shielding----------home stereos don't have this problem since homes are usually made of non conductive wood and we run neutral return conductors for the electric loads-------in homes we have to worry about the actual transformer cores in the individual components, light dimmers etc..........................RC

I understand the cause of the problem now,have never ran across it though. I have always run rca's down 1 side. Thanks for the explanation.

 

[GNRick]

Making progress

Today I taped the RCA wires together and hooked them up. Then I addressed the power/ground issues. Here is what I found.......using a 4 gauge wire hooked directly to the battery was worse than using an 18 gauge wire connected to the junction block in the trunk. The junction block is grounded to the frame. Then I played with the power wires. Using power from the trunk had less noise than using the factory power lead in the dash. However, I would need a relay in thise scenario to turn the radio off with the key. So I went to Circuit City, where my favorite installer hooked me up with a relay. I think I'm on the right track. The engine noise at this pont is only audible at the lowest volumn setting, where you can't hear the music. As soon as I turn up the volumn, the music drowns out the noise. The installer said the relay has a filter which will eliminate the noise completely. Thanks to Richard and Dave and everyone else for their help. :smile:

 

[TurboTnZ06]

Holy shet. All that engineering physics I took in college, all those installs in cars over the last 12 years just for fun (I'm a software architect/consultant by trade) and it only now makes sense- it's the physical loops of wire is why I have noise in my car. LoL I feel like a dummy eventhough I always have to explain how induction works to people when they ask about my mom's induction stove top at holiday gatherings.... Makes total sense now- Thanks!

in almost all cases testing one side at a time will always lead to a misdiagnosis since the noise will usually be worse with BOTH sides connected and either side alone will usually appear quieter------------

let me give an abbreviated explanation of how a signal conductor usually picks up alternator wine------if you are familiar with a transformer you know a few basic things-----current flows through the primary winding and creates a magnetic field in the core-----this magnetic field in turn causes a current in the secondary winding since it also is looped around the magnetic core------the way alternator whine is injected into a signal conductor of a car is exactly the same way-------in a car we don't have a primary winding but we do have current flowing through the conductive chassis/body of the car because all of the electrical components in the car use the chassis as a negative conductor------this flow of current creates a magnetic field within the confines of the car-------any wire that forms a loop within this area will have a current induced into it-----a loop would be defined as a any part of a complete circuit run between two components-----any wire run through this area will have noise if current is flowing in the chassis-------its impossible for it not to have noise-----the goal in a scientific install is to minimize the "loop area" so the noise is below audible levels-----in any system installed in a car with enough gain applied or sensitive enough test equipment there WILL BE NOISE IF CURRENT IS FLOWING IN THE CHASSIS------the larger the loop the more the current and the more loops the more the voltage----------a single RCA run through the car will pick up very little of this noise because the loop area is minimal but it does exist--------a stereo pair of "RCA" will have even more loop area------a comolded pair will have less loop area than a seperate pair of wires------smaller wires will have less loop area than larger wires--------big fat "triple shielded" wires are the worst for noise---------when a pair is run down one side of the car and another pair is run down the other side it is an invitation for disaster since the loop area between opposite sides of the car is gigantic------the best course of action is to keep both pairs of conductors together as close as possible (taping or using loom) so the loop area of the 4 conductors is as small as possible--------of course it varies from car to car depending on actual current paths in the chassis, actual amount of current, vicinity of the wire to the chassis and other factors------BUT the most important thing to understand about this VERY COMMON type of noise is that shielding is TOTALLY ineffective to reduce it---------thats why in the toughest autosound noise cases the quietest wire is extremely small UTP (unshielded twisted pair) as long as there isn't a source of electrostatic noise (such as sparkplug or switching transients) that can only be stopped by shielding----------home stereos don't have this problem since homes are usually made of non conductive wood and we run neutral return conductors for the electric loads-------in homes we have to worry about the actual transformer cores in the individual components, light dimmers etc..........................RC

 

[dnavone]

Problem Solved?

Thanks for the email and the results of your troubleshooting tests... By reducing the loop area created by the outputs of the HU, signal cables, and inputs of the power amps, you reduced the low frequency noise problem. RCA connectors and side-side constructed signal cables tend to pick up the most low frequency loop area noise...

It would be optimal to have all eight (four stereo pairs) of the signal conductors designed to maintain equal geometry with respect any individual conductor... Also, it would be best to have the source end of the signal cable, and the sink end of the signal cable, terminated into close quarters... --- Much closer than female RCA chassis connectors spaced 2" apart!

Thanks again..
Dave

 

[Jarnutt]

This comes straight from dealing with "ghosts" in the sound system for about 7 years, but sometimes, its hard as hell to chase down an alternator whine. Beyond the laws of time and space itself, there have been cases where I couldnt get rid of it, and had to tell my customer, "sorry". alot of times if you throw a filter in there either on the RCA line, or run a common ground wire to all components, you can get rid of it. Most of the problems I have had were with Video systems, where instead of alternator whine, you get screen distortions, like an oscilliscope, the quality of the equipment plays a large role too, most higher end equipment comes with circuitry to combat ground loop noise, and filtering to clean up video noise.

 

[dnavone]

Basic Troubleshooting

Actually debugging an audio system can be straightforward.... And by applying the principles of basic troubleshooting, we can first find the nature of the problem, and second arrive at a solution.

We usually start with step one: Mute the amp(s)... If all is quiet, then we know that the speakers, speaker leads, passive crossover elements, and the power amplifeir(s) are all OK... If there is noise, then we won't have to look any further because until the amp/speakers are quiet, we won't gain much by working on the deck, signal cables, processors, etc...

More later..

 

[Jarnutt]

Actually debugging an audio system can be straightforward.... And by applying the principles of basic troubleshooting, we can first find the nature of the problem, and second arrive at a solution.

We usually start with step one: Mute the amp(s)... If all is quiet, then we know that the speakers, speaker leads, passive crossover elements, and the power amplifeir(s) are all OK... If there is noise, then we won't have to look any further because until the amp/speakers are quiet, we won't gain much by working on the deck, signal cables, processors, etc...

More later..

Not to pick fights with you dnavone, but sometimes the simple solutions are not so simle. On paper such troubleshooting methods work great, and to arrive at such a textbook answer, we would first have to acknowledge that on paper, communism works great too. pulling apart wiring and panels, and disconnecting harness after harness, chasing a problem is still time consuming, and so making it a pain regardless of how simple.

sometimes the source noise may NOT be what it appears in the first place, muting, or turning off the amps may get rid of the noise, but that may not mean the source of the problem is the amp, but maybe a combination of elements including the amps. For example an early 90's Ford explorer that I fought with over the course of almost 6 months on and off. she had alternator whine, only when she first started the vehicle, and not after she had driven it a while. Thats all the information she gave me, after many months I came to find that by when she said, "only when she first started it", she meant in the morning on her way to work. long story short, the whine was due to her defrost wire for her rear window running alongside the RCA cables, and caused noise when she defrosted them on the way to work. Of course higher quality RCAs could have rid her of the problem, but we cant make our customers buy the best every time. After replacing the RCA cables with no luck, I simply ran an isolated ground wire alongside the RCAs and the noise went away. So basically, it may be textbook troubleshooting, or I may not have had as much luck as you in the past, but nobody is perfect, if we were, then we as humans wouldnt push so hard on the door that is clearly mark "PULL TO OPEN"

 

[dnavone]

Audio Troubleshooting 101

OK.. Thanks for the comments.. however, I have to take exception to the last reply... Muting the amplifier = supplying a "known good", which is a signal of 0 Volts with a source impedance of 0 Ohms.. It doesn't get much better than that for a pure signal with a low source impedance.. If a muted amplifier produces anything but 0 Volts at the output, then this part of the audio system must be addressed before continuing the troubleshooting. It's important to understand that Muting the Amplifier is not turning off the amplifier as was mentioned in the previous post.

The reason that it's important to understand muting is that once the amp/speaker part of the audio system is proven free of noise, then we move our muting plug back up the signal path... A muting plug can also be called a dead short. At the bottom of the home page on my website: David Navone - Car Audio Engineering there are a couple of video productions on the construction and use of a muting plug...

One last point.. The term "high quality RCA cables" is totally meaningless to the world of automotive audio. Marketing has produced very expensive triple shielding signal cables that actally pick up more low frequency inductive interference than basic UTP cabling with no shielding.. A good parallel is to look at the telephone and ethernet wiring in your home/office. How much shielding does your telephone system use? The answer is none...

Why is telephone and car audio similar? Because the noise lies in exactly the same bandwidth as the signal. Rectification is not required for noise to be produced in a car audio system.. In fact, most of our audio systems have low pass filtering on the inputs to eliminate the type of noise that shielding would benefit. My partner, Richard Clark, and I have a patent on a particularly low noise signal cable, Delta Factor... and we have studied this subject for many years.

I'm not saying that troubleshooting a car audio sytem is trivial... on the contrary, multiple amplifiers fed by various processors driven by several sources (i.e. iPod, cell phone, CD Changer, AM/FM/Satellite, HU, etc.) can lead to a complex system. The way to handle such a system is to start by Muting the Amps... This basic step is important to logical troubleshooting... And I've been doing this type of work for 40+ years... in avionics, ham radio, home/pro audio, and car audio. Mute the Amp!

 

[54Rich]

guys-----please be patient and when this problem is solved we can all go over exactly what the cause was------how we fixed it-----and why it worked-----as well as why the standard installer voodoo cures have nothing to do with it---------and i will share a printed copy of the troubleshooting algorithm with everyone to download for future use-------my partner dave navone who is a physicist and just darn smart guy developed it over a period of years--------no offense to anyone but guys of his educational caliber don't usually spend much time in car audio install bays------a lot of car audio guys that have had the opportunity to learn from him are much better off because of him and they know it--------nothing secret here----dave has shared his knowledge with installers for years through seminars, books and magazine articles------many of his "students" have moved on over the years to become product specialists with component manufacturers or gone on to even better careers-------dave is a little more of a "friendlier" teacher than i am and much more of a people person----sorry if i have offended anyone------its just that science is science and voodoo is well-----?????................RC

Can you tell I'm board today? Baby sitting a sick 2.5 YO, is not much fun

Anyhow, I think this thread died without the troubleshooting download. I'd love to have it for reference.

Thanks,

Rich

 

[A2000RICH]

Can you tell I'm board today? Baby sitting a sick 2.5 YO, is not much fun

Anyhow, I think this thread died without the troubleshooting download. I'd love to have it for reference.

Thanks,

Rich

send a message to my partner dave and tell him that i asked that he send you a CD with the trouble shooting algorithm -------he is the one that handles that out of the california office---------if you don't get it soon give me a reminder call..............RC

 

[54Rich]

send a message to my partner dave and tell him that i asked that he send you a CD with the trouble shooting algorithm -------he is the one that handles that out of the california office---------if you don't get it soon give me a reminder call..............RC

Thanks!

Is it just someting that can be uploaded to a server? Hate to have him burn a bunch of CD's. I got 5 meg of space sitting doing nothing I could host the file for awhile, until people get a chance to download it. How big is it?

Rich

 

[A2000RICH]

Thanks!

Is it just someting that can be uploaded to a server? Hate to have him burn a bunch of CD's. I got 5 meg of space sitting doing nothing I could host the file for awhile, until people get a chance to download it. How big is it?

Rich

i really can't answer your questions------dave has always handled that part of the business------he will not mind your inquiry................RC