hospital grade or commercial grade receptacles ?

Sorry, Saki70, I was having entirely too much fun. Isolated grounding is highly recommended, if only to make sure that the outlets are indeed grounded properly! You'd be surprised how may homes/apts have screwed up grounding.

One thing to watch for that annoyed a previous spouse... an electrician will install orange outlets for isolated ground circuits, unless you direct him differently. My spouse found the bright orange offensive.

Irvrobinson...How did the orange color affect the sound?

The orange color widened the soundstage considerably. The inter-note silences were also deeper and blacker. The only downside was that I noticed some softening of the micro-dynamics, but I only noticed it when using unbalanced interconnects.

Eldartford:
I guess there are more colorations in Ivr system sound after the change.

Paradigms preclude progress! Keep an open mind and above all open ears!!!

"The only downside was that I noticed some softening of the micro-dynamics, but I only noticed it when using unbalanced interconnects."

I don't know about you Irv but sometimes too much leading edge on the transients of the micro dynamics can sound artificial. I kinda like it when the microdynamics are softened, just a tad.

Seriously though, you might benefit just a bit if you could just eliminate your preconceived institutional thinking and just trust your ears. Often times as not what is seemingly snake oil can fool you. Being skeptical of many things audio I can say with a straight face that I have definitely heard differences in outlets and powercords. I really don't know why this should be but it is real. Don't dismiss Albert Porter too readily, he has invested many years and has listened extensively to many products. You don't mean to say that we're all a bunch of fools and are being duped by a group think plecebo effect, do you?