Another cheater plug thread

After having followed the expert comments on these threads, but without wading much further into the murky swamp of perceived risks and high-consequence/low-probability events (where I misspent way too much of my life), just an added thought or two:

Even in the presence of a rattlesnake, risk of being struck is very, very small. That said, if I knew that one was in my back yard, I probably wouldn't let neighbors or friends back there.

When I had a recent insurance claim on some of my audio equipment, the adjuster asked detailed questions concerning circuitry and connections. Not sure I would have wanted to try and explain how low-risk a cheater plug actually was.

If you've got a $15K system, family and friends in one's home, and ANY identified risk that's easily solved, why not: a) as advised, just spring for a couple of hundred extra bucks that will make the issue go away and might even improve your SQ; and b) then JUST FORGGEDDABOUTIT?

Elizabeth, Plane crashing or bus driving into your home does not depend on you and is therefore not worth discussing. Driving without seat-belts or good brakes is dangerous no matter how small chance of accident is. Similarly, leaving one metal cabinet (that was designed to be grounded) floating while next one is grounded is dangerous. Being irresponsible with proper grounding is not very smart, IMHO, but recommending it to others is much worse.

Something not mentioned is the sonic issues related to lifting a ground.

The problem is a ground loop, you lift the ground and no more hum. This is caused by the fact that some part of the signal chain (amp, preamp) is improperly wired.

For example if the chassis and circuit ground are the same thing, that unit will be prone to ground loop issues. Now to pass UL and CE (in fact any electrical code worldwide) the chassis has to be grounded. The issue is how to deal with the circuit ground if the chassis is grounded, and not have a ground loop.

The solution is simple but you would be utterly amazed at how many companies have not sorted this out! All that is needed is the circuit ground 'float' within the chassis, with all ground points like RCA connectors and the like isolated from the chassis. Then a moderate resistance is used between the chassis and circuit ground. This floats the circuit ground at chassis potential (electrical ground).

The added benefit is that now the chassis shields the circuit without injecting noise, something that results in better sound due to 'blacker backgrounds'.

So, IMO/IME its worth it to get equipment with bugs like this fixed! If done, you never worry about grounds again, and you don't have to mess with exotic (kooky) grounding schemes like a rod in the garden or some messed up stuff that is a recipe for trouble.

I know that may draw some criticism but honestly, get the equipment fixed and you will find out what I am talking about.

I would think that some return to ground is necessary otherwise system noise would travel from box to box. For instance noise induced in the shield has to find return to ground and it is far better to find direct path instead of currents traveling on ground wire of IC (causing voltage drops that appear as signal) to another box that is "closer" to ground even if everything is floating. Floating might also be a disaster in case of static discharge to connector ground since current will go thru all available paths (including signal path electronics) to find return, instead of quick return to local ground. I would use high voltage capacitor about 0.01uF/1kV possibly with 100k-1M resistor in parallel between signal and chassis ground possibly close to input connectors. Hard wired connection (like in IBM PC) is good when we have only one box but otherwise makes ground loops or cause large current between boxes plugged into different outlets when connected together.