Is grounding with RCA is safe?

I am thinking about a DIY passive grounding box, which is a wooden box with different minerals inside. I think it does not take much time to turn what I am having now into a DIY passive grounding box.

Not to take sound quality into consideration, do you think that this solution is safer and less interferes with the accuracy of the system?

This appears to me to be perfectly safe.

As far as the possible sonic consequences are concerned, if the "minerals" are not conductive, and if there are no uninsulated ends of the ground wires making direct contact with each other, it seems to me that all you would be accomplishing is hanging a bunch of antennas off of the circuit grounds of the components.  Which in turn might pick up RFI and conduct it into the components.

If the "minerals" are conductive, or if uninsulated ends of some of the wires are in direct contact with each other, you will have established additional paths between the circuit grounds of some of the components.  Any sonic consequences that may result figure to be unpredictable, IMO.

FWIW, I personally would not consider such an experiment to be a worthwhile investment of time, but that's just me.

Good luck.  Regards,
-- Al
 

@skipskip, if I followed your post correctly I believe you may not be realizing that nothing the OP has done has removed, replaced, or in any way defeated the normal AC safety ground connections of the equipment.

Regards,
-- Al

The following thread will be of interest:

https://forum.audiogon.com/discussions/a-new-ground-benefits-of-introducing-the-synergistic-research-active

Some excerpts:

Atmasphere 6-27-2017
I did a survey of a number of grounding systems by interviewing the owners and having them do a few tests (as best as I can make out, these were similar to the SR, but none of them were SR units).

What I found was that in audio systems where a grounding system made an improvement, universally there were also bugs in the way that the associated audio equipment was grounded, which is why the grounding boxes were helping.

Just my opinion of course, but if the manufacturers of the various products (amps, preamps and the like) in those audio systems were to fix the bugs in their products, the result would be even better and at worst just as good as the (IMO rather expensive) grounding system add-ons.

My conclusion was that if a grounding box was helping, that was an indication that the associated equipment had design flaws in their grounding implementation.

Atmasphere 6-28-2017
All it takes is one component to short out the grounding scheme on the other equipment.

How it works is, the chassis of the equipment should be grounded to the ground pin of the AC cord which in turn is grounded by the house wiring. There is no current on this connection....

... The circuit ground of the amplifier, preamp or whatever is **not** connected to the chassis in a proper setup but is instead ’floated’ at ground potential by a simple circuit which might simply be a resistor or resistor/diode arrangement. In this way ground loops between equipment are prevented and the chassis is allowed to act as a shield while not also acting as a ground return.

If only one piece in the system has the circuit and chassis be the same thing, then its connection to the rest of the system will compromise the grounding of the rest of the system. Now you have to do something about it and that is what these grounding block thingys do- at a tremendous price though, as a better solution would be to simply have the offending piece repaired by the manufacturer.

Almarg 6-28-2017
Ralph, thanks. That all makes sense from a technical standpoint, as far as I am concerned. Question: Could similar adverse effects occur to an audible degree if rather than circuit ground and chassis ground/AC safety ground being connected directly together in one or more of the components in a system, they are instead connected together through a resistor whose value is simply too low? For example, I’ve seen in some ARC designs that resistors as low as 10 ohms are used for that purpose.

Atmasphere 6-28-2017
Hello Al,

The resistor is there to prevent ground currents and often 10 ohms is enough to do the job, just as you see in the old Dynaco gear.

I like a little more myself, and its not a bad idea to place some high current diodes in opposite directions in parallel with the resistor. In this way if a component is damaged and places the AC line on the chassis, a fuse will blow rather than just cooking the resistor.

I’ve not played with the resistor value to see what effect it has, but it stands to reason that a value too low mitigates its use and not in a good way :)

Atmasphere 7-5-2017
If you have a DVM there is a simple measurement that will tell you if the amp/preamp/whatever is properly grounded.

With the unit unplugged and out of the system, the DVM set to the Ohms scale:

The center pin of the IEC connection (or ground pin of the AC cord) should measure a short to the chassis; IOW about 0.5 ohms or less.

If the ground of the audio input connection measures the same then you have a problem. If it seems to measure significantly higher than things are good.

If you have no connection between the chassis and the ground pin of the AC cord then the equipment can be considered dangerous and will not meet UL standards nor EU Directives (CE mark).

And note especially the second sentence quoted from the following post!

Folkfreak 10-29-2017
The [Synergistic Research] active ground block has active components inside as well as a ground connection.

... even passive ground solutions give results, consider for example the Entreq units which have no connection to the AC safety ground at all but still produce the same type of results.

ted_d (Ted Denney of Synergistic Research) 5-1-2019
The Active Ground Block SE has an Active Electromagnetic Cell similar to what is found in our PowerCell line conditioners, the non SE version does not. This (the Active EM Cell) filters high frequency noise out of ground which is significant....

... NEVER EVER plug the Active Ground Bock into anything but the wall. Do NOT plug it into a line conditioner or anything but a wall outlet otherwise you will introduce impedance and crosstalk contamination and this seriously diminishes sound quality.

Regards,
-- Al

In most components the circuit ground is directly connected to the chassis.

I believe that is not true. And certainly, IMO, a **good** design will not connect circuit ground and chassis directly together, as it invites ground loop issues.

As Erik indicated, many designs have a resistor connected between circuit ground and chassis, and many others go even further in isolating them from each other. I know, for example, that circuit ground and chassis are not connected together in most or all Audio Research, Ayre, and Atma-Sphere designs, among others.

Regards,
-- Al

I still have a question regarding your reply:
"In effect what you are most likely doing (depending on the designs of the components) is connecting the internal circuit ground of each component to the chassis of that component and to the chassis of every other component in the system"

I check the ground box from Entreq. It looks like to me that they do the same thing.

Could you help shed some light on this?

The internal circuit grounds of most components are connected to the ground sleeve of their RCA connectors. And since the components apparently have three-prong power plugs, the safety ground prong on those plugs is presumably connected to the chassis of the corresponding component.

So since you have connected the ground sleeve of an RCA connector to the safety ground pin on the power plug of each component, and the safety grounds of all of the components are connected together via the outlets and the associated AC wiring, you have most likely connected both the circuit grounds and the chassis of all of the components together.

I have no knowledge of Entreq products, but if in fact they do the same thing I personally would not want to use them.

I searched online and learn that ground loops can destroy audio gears in long run. Is it true?

I can’t envision a means by which a ground loop could cause damage, other than in the very unlikely scenario I described in my previous post. A ground loop could, of course, have adverse sonic consequences, and degrade the accuracy of the system. Which may or may not be subjectively preferable, however.

Regards,
-- Al

The only way that occurs to me in which that might be hazardous to the equipment is in the very unlikely event that an insulation failure develops within a component, resulting in the AC line voltage being applied to the chassis of the component and from there via the AC safety ground connection and the wires you have installed to the internal circuit grounds of the components, during the brief amount of time it would take the breaker to trip.

However, as Roberjerman indicated you are making the system very susceptible to ground loop issues. In effect what you are most likely doing (depending on the designs of the components) is connecting the internal circuit ground of each component to the chassis of that component and to the chassis of every other component in the system. Thereby in effect changing the designs of the components, as well as the ground paths between them.

While you have found the results of those changes to be subjectively preferable to you, you have therefore most likely compromised the accuracy of the system.

Regards,
-- Al