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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
kijanki's avatar
kijanki
4,428 posts
 
Newbee, Interconnects make connections between signal grounds that most likely aren't chassis grounds.
rower30
211 posts
 
If your chassis is NOT grounded to the wall outlet ground it will be floating above ground. With a VOM set to continuity, touch the chassis to the wall oulet "ground" and it should measure continuity showing it is indeed grounded. Removing a chassis ground might break a ground loop and sound good but it is deadly if you touch the unit's chassis, and any conductor to ground. If there is a fault in the system, the system is looking for a ground through YOU someday, and to earth. THAT is WHY the chassis has to be properly grounded at all times.

I would heavily advise to not let your chassis float ungrounded, and fix the ground loop.
atmasphere's avatar
atmasphere
11,772 posts
 
Removing a chassis ground might break a ground loop and sound good but it is deadly if you touch the unit's chassis, and any conductor to ground.

Amend to 'could be deadly'. Its that 'could' that is why there are things like UL and CE directives.

In the old days the RCA ground was the same thing as chassis ground in a lot of cases. IMO that is a bad move, and the better manufacturers even in the old days avoided the practice.

The funny thing is that proper grounding also results in better sound. You would think more manufacturers would want to be on board with this....
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