AndrewPG,
I suspect you're right about power line noise in the U.S.

I used to live in San Jose, and the noise there (as measured by both an Entech power line noise meter, and my old [now sadly departed] oscilloscope) showed terrible noise levels. Measuring the output after a Shunyata conditioner showed unmeasurably low noise on the Entech, and much smoother waveforms on the oscilloscope.

I now live in San Diego, where the power line noise is even worse! Same result with the Shunyata conditioner. Unmeasurably low via the Entech. Unfortunately, I no longer have an oscilloscope, so I can't compare the visible waveform change.

I don't want to politicize the forum, but I completely get your comment about not wanting to buy U.S. products at the moment. No one can predict the future, but I hope we come back to something approaching normalcy again.

Best regards.

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