Cheap grounding solution

Well it did cost you a PC you could otherwise have sold. But yeah, okay, I get it. Is this better than ordinary wire? Probably would be, I guess. But did you try it that way first just to see? How many Krissy filters do you have? If none or if that question doesn't even make sense PM, we need to talk. ;)

Alternatively terminate with RCA plug not connecting the centre pin and use spare RCA input on Pre or DAC

The UK has a different method of grounding an electrical service in a residential dwelling unit than the USA as I understand from what I have been able to read about it. In the US there is a good chance doing what you did in the UK would cause a ground loop hum here in the US when the audio equipment is connected together by wire interconnects.


Also worth mentioning, well designed audio equipment the circuit ground of the equipment is not connected directly to the chassis of the equipment as the EGC, (Equipment Grounding Conductor) is required to be. Your added EGC connects the circuit ground of the equipment directly to the chassis grounded EGC.

An EGC and or earth ground does not possess some magical, mystical power that sucks nasties from an audio system. If anything it can cause more harm that good. An EGC’s purpose is for electrical safety.

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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 problem. 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."

Henry W. Ott

Who is Henry Ott?
http://www.hottconsultants.com/bio.html
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I am obviously not in any way a technical expert but it seems similar devices (Gutwire) are positively reviewed by the likes of audiobacon, audiophileman and 6moons and sold by the CableCo. Seems another religious war is in the making.

You lost me at 

...  and insert power plags into a switched of mains socket, ideally on a different circuit.

Do you mean you plug your modified to ground-only cable into a wall socket that is turned off? The other side goes onto a grounding lug on the device?

I am assuming on the socket where you plug in the C13 plug of your "regular" power cable into your device you would want that ground conductor disconnected yes?