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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
rodman99999
5,988 posts
 
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)!
newbee
4,751 posts
 
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. :-)
sleepysurf
121 posts
 
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?
atmasphere's avatar
atmasphere
11,588 posts
 
Newbee, if you use your CDP normally, probably not much will come of it. But if it gets dropped or abused in such a way that the power switch or AC power is able to contact the chassis, then you may have a problem. If the chassis is ground, a fuse will blow and all is well. If not, it may be possible to start a fire or create a shock hazard in the system.
newbee
4,751 posts
 
Atmosphere, don't the rca's connecting the CDP to the pre-amp effectively ground the CDP chassis?
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