Enough noise reduction?

@holmz 

I'm still doubtful a lab power supply is used. It just doesn't make any sense. A lab 'bench' power supply provides DC, not AC. Also, these components are consumer products meant to operate off of standard household power. If you want to measure and test them, wouldn't you want to know the performance given wall power?

No, I don’t think so.
One would want just the noise and distortion from only the unit.

But many would also want to know how the unit operates with dodgy power.

Since we do not know what different cities, countries, and individual houses power looks like, then the easiest is just use pure sine wave power.

Do it right and install an isolation transformer. That protects your system, improves the sound, and takes power cables out of the equation. I've done the tests and I have three isolation transformers in the utility room, 'cause they tend to hum when they're working hard.

Sort of like Jiminy cricket, they whistle when they work? @terry9 

Just so. @holmz 

if you're going to get power cords the best ones to get are the rectangular OCC single crystal wire even better than the round OCC single crystal wire. Neotech makes some good ones, and just so you know Neotech makes the OCC wire for all the companies that are charging an arm and a leg for it, their own line is reasonably priced and their top line is not cheap but way cheaper than the other guys that are charging double what Neotech charges for theirs.Check out the Amazon which is their OCC silver single Crystal rectangular wire and the Sahara which is their rectangular copper OCC wire.