Another cheater plug thread


OK. So on a couple of other threads, opinions of cheater plugs to tame system hum range from "If it works use it" to "you're going to die in a fiery inferno." In my case, I used a cheater plug between my power supply and my pre-amp to finally get rid of a year-old hum problem. the power supply is a PS Audio Ultimate Outlet with only two outlets that supplies only my amp and pre-amp. Because the PS is still grounded - I think - all I did was break the ground circuit between the two components. So the question is, do I still have any grounding on my pre-amp here, just on the basis of being plugged into a grounded power supply? I wouldn't think so, but I'm not an engineer. Also, what is the benefit of being grounded vs. ungrounded in this situation?

Ready, set, fight!
grimace
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.
I strongly agree with Atmasphere and some others. Fix the problem, don't cover it up and cross your fingers hoping for the best. Find the cause of the ground loop (it is fairly simple but tedious to do this), and either fix or replace the faulty piece of equipment. Do not use a cheater plug. This is lazy and seriously stupid. All the more reason to audition equipment in your home/system before you purchase it. If a ground loop occurs during auditioning, then find the culprit and remove it or fix it.

Also, anyone that recommends to lift the ground, use a cheater plug, not use seat belts and other dangerous things, are not your friends and are not looking out for your best interest.

enjoy
ATTENTION- Anyone with Dynaco, ARC, McIntosh, Marantz or Conrad Johnson(tubed components), that lack a grounded power cord: Keeping/using that equipment is dangerous and not in your best interest. Send it to ME, IMMEDIATELY(I'm your friend and will take all the risks)!
Hi Minorl, Great advise. You sound like a very knowlegable person so perhaps you could answer a question I have.

I have an amp which is grounded properly driven by a pre-amp which is grounded properly. When I plug in a CDP it creates a ground loop and I get a hum thru the speakers. When I put a cheater plug on the end of the CDP power cord the hum goes away.

What risk to I incur in operating the system with this cheater plug in place? Why is that so? So I better understand, please create a situation where the risk you describe will be encountered. Please take it beyond electrical theory. If you can back it up by referring to an actual occurance that would be better yet.

In anticipation of the thoughtful reply I will receive, thanks. Perhaps I'm not lazy or seriously stupid, just a little bit ignorant. :-)
Another "non cheater plug" solution for a difficult to isolate ground loop might be the Ebtech Hum X device (available from Amazon and elsewhere). I've been using a "cheater" with my C-J CT5 for 3 years, and just ordered the Hum X as a safer alternative. I don't believe the 6 amp max capacity of the Hum X will be an issue with the preamp current draw.

Anybody else using one of these?