Rerurn to Romy the Cat's Site

SOS, as a starting point, it does not seem at all odd to me that adding an "other" piece of equipment to the electrical chain might require a reconfiguration of the system ground scheme.  Of course, the phono stage is the worst case for hum, PP or no.  May we suppose that you used well-shielded phono cables that are well away from the PP unit?  Did you "dangle" the "downstream" shield connectors and ground the "upstream" shield connectors?  Do you use a dedicated, low-resistance ground rod/wire for the phono gear?

I have found it is normally the case that all gear has to be plugged into any ONE "power conditioner" or "regenerator", or - at least - "other" gear must be on a totally separate circuit (eg, not the other 1/2 of a 220 line, sharing a neutral).  Properly designed amps, in particular, should generally have their gound wires "lifted".  In any case, the PP (or any switching device) is best kept at a distance from other gear (and leads), since it also broadcasts its filth over the airwaves.  

Taking the foregoing into consideration, yet, one would not expect the PP itself to "add" typical AC "line hum".  I agree with Romy that it "sounds like" the hum you've experienced is the result of some sort of ground-related mishap that might be/might have been solved by due diligence in the course of system-specific ground sleuthing and by re-configuring the grounding scheme, "as necessary".  In your specific case, you probably know that it is often a good idea to run a ground from the TT motor straight to the dedicated ground line.  I can share that this is the only thing that works in my system.

If you read back over this very long thread you will quickly gather that I have expressed putative disappointment as contempt for PP's ridiculous "QC", and I have literally waited for years for some sign that PP have finally developed and integrated a viable QC program.  Meanwhile, during the course of my waiting, I have come up with no alternatives to the PP.


Best regards,
Paul S

Rerurn to Romy the Cat's Site