@mijostynmakes a good point. If you’re really interested in obtaining a low impedance ground for audio; you might consider your water main pipe as the lower of the two. Of course we all know that our water main ground is connected to the grounding bus bar in our circuit breaker boxes (right?). The main earth electrode (your ground rod or rods) is/are also connected to this same grounding bus bar.
I measured the ground resistance of my earth ground connection on my water pipe, and it was 0.35 ohms, while my ground rod measured 15.0 ohms. I only have one ground rod, but I’m planning to upgrade that to a total of 3 or 4 in the future. What I’m getting at is making your water main coming into your house (for those of us that have city water) a ground priority.
You can make sure this ground delivers ultra low resistance to your circuit breaker box bus bar by making sure it’s connected between the two with a #4 AWG wire or larger (#3 AWG or larger). If you already have this in place - excellent. Making also sure the water pipe ground connection is also clean with little to no oxidation. Improving this water main connection to circuit breaker box is a task I highly recommend you have an electrician perform (if you're a homeowner).
I use crushed charcoal with quartz crystals in my DIY ground boxes. Some ground rods are buried in a trench horizontally instead of vertically. Drilling/ driving not required. Just a thought.🤔
My question is what’s the optimum audiophile fill material to surround a pure copper earth rod? This Bentonite clay slurry or something else?
I just got a 6 foot pure copper earth rod and have no chance of hammering it through the rock under the top soil here. So given I will be getting someone in with an long auger to drill a hole down that far it becomes a good opportunity to use a custom backfill to surround the rod. But I do not know what to use.
Seems like a bit of resentment. Fremer’s outside generator installation screwed up his sonics big time. He had to spend the $ or uninstall the generator.
As always, it’s best to allocate/budget our limited $ wisely to try to get the best performance out of our audio chain. Spending $ to lowering the noise floor beyond what we can hear and/or what our audio chain can reproduce is usually a bit foolish spending. It is also usually best to address the weakest link in our audio chain. Fremer’s Uber system is transparent enough and his trained hearing is good enough to hear minute changes/upgrades.
I was hoping you would respond to my above post in response to yours.
My post, 10/21/2021 9:03am.
It’s not often to read a post where someone with your back ground, can backup their findings with actual hands on testing with measurements. I don’t doubt for a second what your test engineer suggested driving the ground solved the problem you were having. But do you know for sure why it did?
1) How old is the building? The reason I ask as a building ages the soil under a concrete slab, floor, that is on poured on grade will dry out. 2) What is the length of the ground rod that is driven into the earth through the drilled hole in the concrete floor? 8ft? Less?
3) By chance was the rod to soil resistivity, resistance, checked using the proper type of test equipment? If tested what did it measure? Less than 5 ohms? If not tested the rod to soil resistance could actually be high. If the resistance is high then basically it would be no different than floating the chassis of the piece of test equipment above ground. Or at the very least equal to a resistor, resistance, in series with the test equipment and earth connection...By chance did the test engineer repeat the same test with the ground rod ground wire lifted from the piece of test equipment? (Floating the test equipment chassis above ground.)
4) If the test equipment is made to be used on airplanes I can’t help but wonder why you are not using a medical grade type Isolation transformer for a power source for the testing equipment.
One thing I have learned over the years about branch circuit wiring is the type of wiring used and the wiring method used for installation can make a difference on how well a circuit will perform.
A true dedicated circuit should not share the same raceway, conduit, or cable assembly with other branch circuits. Installing more than one branch circuit in the same conduit can/will cause induced voltage, as well as noise, from one current carrying circuit conductors to the other. Also when an insulated EGC is pulled in the conduit the current carrying circuit conductors can induce a voltage, and noise, onto the insulated EGC. This is true even for a dedicated circuit installed in a dedicated conduit where the hot, neutral, and insulated EGC are installed loosely, randomly, in the conduit. Twisting the current carrying conductors together and installing the EGC just along side the twisted current carrying conductors in the conduit greatly reduces the induced voltage onto the EGC.
FWIW: A test of a dedicated ground rod not bonded, connected, to the electrical service main system ground. (Grounding Electrode System).
A while back I drove a 5/8" x 8’ ground rod in the rock garden at the back of the house to use as a dedicated test grounding electrode. The driven ground rod is probably a good 70’ straight as the crow fly s, from the electrical service’s three 10’ each driven ground rods. I did a quick check measurement today and the difference of potential, voltage, from the test ground rod to the electrical service grounding electrode system measured 347mV. ( Meter, Fluke 87 mulimeter).
Project ground for billionaire audiophile. The Earth's core is thought to be iron. Iron is a pretty good conductor. All that is necessary to reach it is a ground rod about 3000 miles long (and a big hammer). This will be an excellent ground but will probably melt because of the high temperature down there. So you will have to keep on hammering.
Perhaps more practical... 1. In another topic I suggested a separate earth for audio system circuits to remove earth loops with other circuits powering noisy equipment
2. If ground is dry around your ground rod, water it every few days or install a drip feed.
@lowrider57 Thanks for the Fremer link which describes the solution to his major audio quality degradation after installing an external electrical generator for power outages. Learning a lot of useful info.
You want a low impedance path to ground and that isn’t easy to achieve. I’ve wondered how you can get around this. Multiple grounding rods should help.
Make sure that if using multiple rods, the scheme should be designed a single point ground - which IIRC the rods are connected in series vs parallel, otherwise the noise will be going from one rod back into another rod and a lightning strike may create an EMF impulse to fry your electronics.
There are some DOD research papers on the web somewhere, have not read them for years. Then there is the Ma Bell triple point grounding system. Even water table management is going to be required. Then you start getting into a rub in that the earth can become a source of noise in your system. This where a local knowledge of the geology of the area needs to be taken into account. Best bet is to find out what Ma Bell and Sprint did in your local area and work from there. Survey says...
Yes, I did watch the video. It was pretty interesting to watch.
I
don’t think I’ve ever seen Cadwelds (Trade Name) used in residential
for connecting the ground wire to the ground rod. That welded connection
is forever.
One thing for sure Fremer was ready for a new electrical service. Did he say how old the house was?
The ground rod is for over voltage from anywhere other than your home. Lightning, transformers, surges, but your home? You don't need it to complete the circuit, but you need it to have self protection, quicker protection, safer protection. Unless your home is prone to lightning strikes, use lightning rods, like in the movie "Powder".
Lightning strikes or recurring surges really suck.
Solar power isolation? I'm getting ready to install solar, this should be fun.. I'm thinking a solar trailer, or solar storage sheds with solar on top, and onboard batteries. Easier to maintain vs crawling on a 8 &12 pitch roof..
Millercarbon’s first post might sound like a joke (and I assume that was
the intention), but there’s an element of truth to it. Ground rods in
dry, low quality soil (common conditions) are not ideal. You want a low
impedance path to ground and that isn’t easy to achieve. I’ve wondered
how you can get around this. Multiple grounding rods should help. Some
jurisdictions require at least 2. So would keeping the soil around the
ground rod wet. I have to imagine there is at least one audiophile on
this forum that has set up a sprinkler system to automatically water the
area near the ground rod to keep electrical conductivity with the earth
high. I’ve also wondered if putting a ground rod in a river bank or
stream would meet code because that would for sure solve the problem.
Right. I find dry prose to be so, uh, dry. I say, variety is the spice of life!
Besides, everyone already knows only five nines pure copper rod extruded with long grain crystals and cryogenically treated are the only acceptable grounding rods. Then just as the room is the most important element in a system the ground is the most critical element in the, er, ground. If you have the bad luck to have built on poor soil this can usually be alleviated by bulldozing down to bedrock and backfilling with a minimum 20 yards of topsoil containing a minimum 8% herkimer diamonds and mahgister sandwiches. Or you eat the mahgister sandwiches while digging, I never could get that part straight?
First of course you did a perk test for soil drainage, and have automatic irrigation to precisely maintain soil saturation as monitored by electrodes placed no more than 1m apart around the ground rod.
Be sure to allow 200 hours for your ground rod to burn in, warm up your ground rod before listening sessions, and whatever you do suspend the wire going to your ground rod above the ground so it doesn't touch the ground until it reaches the ground. Seriously.
My test engineer suggested sinking a ground rod through the floor right next to the test stand so that the chassis could be grounded. Our facilities mgr was not on board with that plan until we showed him that the building ground was floating at 500+ mA! The ground rod worked. To be effective the ground wire must be thick and short. The ground rod must be near the equipment. The ground was connected to the chassis only.
@ tonywinga I have attended numerous Power Quality seminars over the years and this type of discussion always comes up. Usually the equipment comes from Europe. Specs for the equipment will say a ground rod shall be installed next to the equipment and connected to the metal frame of the equipment or connected to the provided ground lug.
The electrician follows the specs *but* still connects the branch circuit wiring EGC (Equipment Grounding Conductor) to the metal frame of the equipment as required by NEC. I bet you see a problem... (Meets NEC. Aux ground rod is allowed as long as NEC 250.54 conditions are met.
So the manufacturer’s Tech comes to see what is causing the problem(s) with the equipment. Where does he look first? "Well there’s the problem"... His equipment is connected to the building’s System Ground, (Grounding Electrode System) by the EGC. He tells the electrician his equipment has to isolated from the building grounding system and only connected to the earth driven ground rod beside the equipment.
Not only dangerous, it violates NEC. In the event of a Hot ungrouned conductor to metal frame ground fault how does the ground fault current return to the source? Through the earth? Not hardly. The breaker at the electrical panel will never trip. What protection will a person have from receiving an electrical shock if he touches the frame of the energized equipment with one hand, and his other hand, or some other part of body, is in contact with a grounded object that is connected, grounded, to the building System Ground? None! No protection at all!
Here is a short video about the use of an aux ground rod. When watching the video substitute the whole house generator with audio equipment. https://www.youtube.com/watch?v=gg4wBI7bWgI
Millercarbon’s first post might sound like a joke (and I assume that was the intention), but there’s an element of truth to it. Ground rods in dry, low quality soil (common conditions) are not ideal. You want a low impedance path to ground and that isn’t easy to achieve. I’ve wondered how you can get around this. Multiple grounding rods should help. Some jurisdictions require at least 2. So would keeping the soil around the ground rod wet. I have to imagine there is at least one audiophile on this forum that has set up a sprinkler system to automatically water the area near the ground rod to keep electrical conductivity with the earth high. I’ve also wondered if putting a ground rod in a river bank or stream would meet code because that would for sure solve the problem.
I'm not advocating adding ground rods but here is my experience as an Eng Mgr over Test Equipment in an Aerospace Mfg plant. We made product that operates in the 0-10 mA range. So the test equipment must be very quiet in order to generate clean plots. We started having some noise issues of say 0.5-1 mA which is enough to make the plots look bad on one of the test stands. My test engineer suggested sinking a ground rod through the floor right next to the test stand so that the chassis could be grounded. Our facilities mgr was not on board with that plan until we showed him that the building ground was floating at 500+ mA! The ground rod worked. To be effective the ground wire must be thick and short. The ground rod must be near the equipment. The ground was connected to the chassis only. Adding ground rods just because may not be wise. Proper measurement and analysis of the electrical noise should be done first and then determine the best course of action. BTW- our products fly on airplanes. Therefore, they are operating in the 0-10 mA range with no earth ground.
@jea48 2 rods tied to the panel’s ground buss bar and 6’ apart, correct?
@lowrider57 ,
I assume you are referring to the earth grounding for an electrical service. "The Grounding Electrode System".
6’ apart is the minimum distance required by NEC. The ground rods can be, and is better, if they are at least the length of the rods apart. (8’ rod, 8’ apart). As I remember, Just going from memory, IEEE recommends the ground rods should be twice the length of the rod apart. (8’ rod 16’ apart).
So why don’t electricians install the rods farther apart? Because they only have to follow the NEC and the AHJ (Authority Having Jurisdiction). FWIW, NEC is bare minimum electrical safety standards, requirements. Time = money. The further the rods are driven apart from one another the more hand digging to bury the #6 solid bare copper ground wire that will connect the rods together. Add to the labor cost is the additional cost of the longer #6 solid copper ground wire. Why do electricians use 5/8" x 8’ ground rods? Because that is the minimum diameter and length required by the NEC.
FWIW, for my electrical service I drove three 5/8" x 10’ ground rods about 15’ apart from one another. I used #4 solid copper ground wire instead of the minimum NEC required #6.
What’s the advantage of using 2 rods on a simple residential service panel?
The NEC only requires one ground rod IF it has a rod to soil resistance of 25 ohms or less. So the electrician drives one ground rod. The electrician calls for an inspection. The inspector sees there is only one ground rod. The inspector asks the electrician to see the certified resistance test report proving the ground rod to soil resistance is 25 ohms or less... It’s cheaper just to install the second ground rod. Funny thing, if only one rod is installed and a rod to soil resistance test was done, and the resistance was say 100 ohms all that needs to be done is to drive another ground rod. No further testing is required by NEC.
The main reason for connecting the electrical service equipment and service neutral conductor to earth is for lightning protection. The lower the ground rod , (Grounding Electrode System), to soil resistance the better. IEEE recommends for commercial and industrial electrical services 5 ohms or less.
Honestly, my first post ought to have been sufficiently sarcastic enough to let the OP know he's on a fool's errand. Do we really need to keep hammering on it? Audiophiles. I guess we do. As you were then.
I’m wondering what true audiophile rod made from OCC copper would cost and would it provide better sonic,s . I bet it would ,
It wouldn’t do a darn thing...
The earth does not possess some magical mystical power that sucks nasties from audio equipment.
Grounding Myths
"Electromagnetic Compatibility Engineering" by Henry Ott
3.1.7 Grounding Myths
More myths exist relating to the field of grounding than any other area of electrical engineering. The more common of these are as follows:
1. The earth is a low-impedance path for ground current. False, the impedance of the earth is orders of magnitude greater than the impedance of a copper conductor.
2. The earth is an equipotential. False, this is clearly not true by the result of (1 above).
3. The impedance of a conductor is determined by its resistance. False, what happened to the concept of inductive reactance?
4. To operate with low noise, a circuit or system must be connected to an earth ground. False, because airplanes, satellites, cars and battery powered laptop computers all operate fine without a ground connection. As a matter of fact, an earth ground is more likely to be the cause of noise problems. More electronic system noise problems are resolved by removing (or isolating) a circuit from earth ground than by connecting it to earth ground.
5. To reduce noise, an electronic system should be connected to a separate “quiet ground” by using a separate, isolated ground rod. False, in addition to being untrue, this approach is dangerous and violates the requirements of the NEC (electrical code/rules).
6. An earth ground is unidirectional, with current only flowing into the ground. False, because current must flow in loops, any current that flows into the ground must also flow out of the ground somewhere else.
7. An isolated AC power receptacle is not grounded. False, the term “isolated” refers only to the method by which a receptacle is grounded, not if it is grounded.
8. A system designer can name ground conductors by the type of the current that they should carry (i.e., signal, power, lightning, digital, analog, quiet, noisy, etc.), and the electrons will comply and only flow in the appropriately designated conductors. Obviously false."
The ground rod referred to in the link states copper material $550.00 . I’m wondering what true audiophile rod made from OCC copper would cost and would it provide better sonic,s . I bet it would ,
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