Looking for ac outlet with no sonic signature

I love the Porter Port i bought here on AGon from Albert Porter.
It allowed more air and soundstage without any tonal issues.

How would you know if an AC outlet had no sonic signature?

I would assume if it didn't make it to bright or to warm.
I can tell if I put an IC in my system and it colored the tone. The same thing, let your ears tell you if the tonality has changed.

"let your ears tell you if the tonality has changed" And how do we compare the before and after? Sorry, but I have to ask - 'cause I'd bet that it's pretty hard to directly A/B that setup.

Human auditory memory last maybe 10 seconds, and on top of that as a species we're kinda notorious for accomodation and similar phenomena of perception. If we somehow cannot arrange some way to do a fairly direct comparison then it's awfully darned hard to claim similarity or difference 'cause our mechanisms of perception just cannot support those claims.

Of the many we offer, we have found the Wattgate 381 Gold the be the most neutral