Lowering House Grounding Impedance


So, I’ve finally gotten to a place where I’m pretty happy with the pieces of gear in my system. I know, I’m surprised too. Recently, however, I read about lowering the impedance to ground as a potential improvement and thought I’d give it a try. I’ve done quite a bit of tweaking to get to where I’m finally happy but I had never really looked at the grounding situation for my house, other than to make sure the utility panel was tidy and connected up right. In reviewing my house’s grounding to earth situation, I found that it didn’t have one! My house was built more than 50 years ago and they relied on grounding to the cold water pipes. This was fine while there was 100 feet of 3 inch copper pipe running to my well but when we replaced that pipe with plastic my grounding was gone. Initially, I drove two 8 foot copper clad grounding rods and bonded them together and grounded the external utility panel to them. I was really surprised that the difference the good grounding made to my system, it really removed a layer of haze that I didn’t know was there. Like cleaning a window that is already fairly clean, just added clarity. As I understand it, the lowering of the ground potential is what is responsible for the increase in sound quality. Has, anyone else experimented with improving their ground situation? 
hollandw
Try shaking a magic chicken’s foot at it. You will be truly impressed. Even more than having boutique fuses. 
The magic chicken foot thing sounds like snakeoil sleepy. Grounding, not so much...
I have.  I added a clean ground to my system, rather than use the house ground.  I was amazed at how clean FM reception became.   I had two FM tuners, one analog and the other digital but both improved significantly.   Not only was it cleaner, the music was more coherent as well.   I did not hear any improvement on the other sources though.  
To be clear, you are not allowed to willy nilly use a random new ground. 

You may add ground rods, but all must be bonded together. This ground should be bonded to the neutral at exactly one place: The service entrance. 

Anything else is a life safety issue and prohibited. 

Best,

E
spatialking95 posts12-05-2018 11:19pm

I have. I added a clean ground to my system, rather than use the house ground. I was amazed at how clean FM reception became. I had two FM tuners, one analog and the other digital but both improved significantly. Not only was it cleaner, the music was more coherent as well. I did not hear any improvement on the other sources though.
Not sure why the isolated earth ground connection would increase the reception. I would suggest lifting the isolated ground entirely and listen for any changes one way or the other. My guess is you won’t hear any difference .

As for the electrical safety aspect of the isolated earthed electrode you have now you do not have a low resistive path for ground fault current to return to the source in the event of a hot line to chassis fault.
You also have a greater chance of a nearby lightning strike transient interring on the isolated earth electrode and damaging your audio equipment.

If you want to experiment with a separate earthed ground rod and still meet electrical safety code you can but it must be connected to the branch circuit equipment grounding conductor. The branch circuit equipment grounding conductor must not be lifted from the source electrical panel equipment ground bar. The NEC calls this grounding electrode an "Auxiliary Grounding Electrode". 2017 NEC 250.54.... I would not recommend it though. It just adds another path for a near by lightning high voltage transient not to mention more mother earth noise on your audio equipment.

If you think you need a better connection to mother earth for lightning protection, there in a lower soil resistance, (IEEE recommends 5 ohms or less), you can drive as many ground rods as you want. That is providing they all tie together with a minimum copper wire size of #6awg and then is connected, bonded, to the electrical service entrance neutral conductor. The same point as the existing grounding electrode conductor that is connected to earth.
Jim
It needs to be said that my grounding exceeds code requirements with everything bonded together and hooked up by a licensed electrician. I bought the materials and drove the rods but I let a licensed professional do the final hookup so I have a receipt. I vehemently concur with all here that there can only be one grounding path, with all rods properly bonded together! I started my journey to a lower grounding potential while looking at some of the Nordost products, one of which advocates an additional ground! They do have a caveat in their literature but I can’t immagine what would happen if a close by lightning strike tried to equalize its potential through my house to the other ground. I’m no engineer but I’m going to bet you would be lucky if it just wrecked your gear and didn’t burn the house down. Moreover, I’m sure the insurance adjuster would be happy to find that he could avoid paying out due to a not to code grounding solution.
What you described is the code requirement currently, as I understand it. The grounding connection is a safety requirement. Barring an electrical issue, it shouldn't be doing anything at all. Again, that's how I understand it.
An aftermarket power cord, higher grade wall receptacle, or fuse built for audio purposes shouldn’t be doing anything either - but they do. I don’t understand it either but I can tell you that I listened, went and did the work to effect a good low impedance ground, then listened again and heard a difference. Without telling her what to listen for, I asked my wife if she heard anything different and she identified the same “removal of haze” as I had heard and I’m pretty sure I’ve never even used that terminology around her.
I use 2 x grounds together just in case, one is the cold water pipe and the other is a copper clad earth stake driven deep into the ground. as earth stakes are sometimes not so good if the ground is low in saline content.

Cheers George
builder3116 posts12-07-2018 8:36pm

What you described is the code requirement currently, as I understand it. The grounding connection is a safety requirement. Barring an electrical issue, it shouldn’t be doing anything at all. Again, that’s how I understand it.

Barring an electrical issue, it shouldn’t be doing anything at all.

But with the absence of the mother earth connection could it have been adversely causing a problem?

Is it possible there was electrical noise being introduced on the service neutral conductor at the utility power transformer neutral earth connection? I suppose with the proper test equipment it could be checked by lifting the mother earth connection at the house electrical service again.

Some background.
The secondary neutral of the utility power transformer is connected to mother earth at the transformer location. In fact a mother earth connection, I believe, is made at every power pole and connected to the high voltage neutral conductor. At each utility power transformer the secondary neutral conductor is connected to the high voltage primary neutral conductor and then connected to mother earth. (Same method is used for underground high voltage power lines and pad mounted utility power transformers.) All for lightning protection as well for a hot high voltage line and or a hot secondary line ground fault event.
As you can see multiple mother earth connections galore. All kinds of possible stray voltages/currents passing/traveling through the earth. Another reason Isolated earth ground rods should not be used for audio equipment.

The 2 new ground rods, (Grounding Electrode), the OP connected to the electrical service entrance neutral at the electrical panel may be a lower ground (earth) resistance than the one at the utility transformer. My guess it is. What effect would, does, the lower resistance earth connection have on electrical noise traveling on the service neutral conductor from the utility power transformer earth connection? Beats me. Is the noise traveling on the service neutral conductor shunted back to mother earth at the new ground rods? Is there a closed circuit? Could it be tested using test equipment and lifting the earth connection for the test? Someone like Al, (almarg), might be able to answer that question.
Jim.
.
.
https://en.wikipedia.org/wiki/Stray_voltage

Jim, interesting, and I don't know the answers. I wish I had a better understanding of the real world differences and interactions of the grounded (neutral) and grounding conductors. Thanks for the link, I'll check back.
Some background.
The secondary neutral of the utility power transformer is connected to mother earth at the transformer location. In fact a mother earth connection, I believe, is made at every power pole and connected to the high voltage neutral conductor.
Correction:
In fact a mother earth connection, I believe, is made at every power pole and connected to the high voltage neutral conductor.
Only at the utility power transformer locations.
builder3119 posts12-08-2018 6:30pm

Jim, interesting, and I don’t know the answers. I wish I had a better understanding of the real world differences and interactions of the grounded (neutral) and grounding conductors. Thanks for the link, I’ll check back.

I wish I had a better understanding of the real world differences and interactions of the grounded (neutral) and grounding conductors.

The "Grounded Conductor" (neutral conductor) and "Grounding Conductor" (equipment grounding conductor) are at the same zero potential at the main electrical service equipment (main electrical panel) where they are both connected together. If RFI/EMI is on the service entrance neutral conductor wouldn’t it also be transferred onto the grounding conductor (equipment grounding conductor)?