Hi ricred1. Have you unplugged all the other cords while you were testing Shunyata? The cords with different designs can interact sometimes as they introduce their own signatures (capacitance, inductance...)? Have you tried to listen to your system for at least 24 hours before switching to other tested cord?
What I have realized while comparing an fantastic AQ NRG 1000 with Shunyata Zitron Alpha HC is that in every possible area Shunyata was better. Zitron technology simply made that jump over AQ.
I can not imagine what would Shunyata Sigma NR bring to my system, and I even do not want to think about it, as it is beyond my payment level in this moment, but if I had that money, I would rather think of investing into Shunyata Denali filter and used Shunyata Zitron Alpha HC. This would bring your system to a new level.
Regarding here mentioned AQ new lines of cables... I do not believe it until I see it. I just believe my ears and testing of components in my system for a while. Maybe AQ really made something very good here, but let's first see it to believe it.
When talking of Shunyata, yes, it can reveal a lot of low frequency information that you have never heard before, as it was masked, and yes, to some systems it will appear too much, as this systems that we audiophiles are assembling were carefully built to a level which covers for that part of frequencies which we are missing (which is now revealed by Shunyata)... so in the end you might think that you have too much bass. But in fact after Shunyata treatment, all of information (including bass) is revealed and clean and punctual, right as it is coming from from the wall or your power amp.
For example, I use all around Shunyata in my system, so in the end I do not need any subwoofer. I really do not miss this box which introduces new problems to my room.
I know that some power amps do not match some power cords (and signal and speaker cords). This is due to fact that some particular power amp and particular cable tend to maybe reveal more of one information and then the result is what? Probably emphasized one part of frequency.
It is down to Power Amp design and cords design...
But to be sure if some power cord is good for your system, the tests have to be conducted well.
I must say that I've had non conventional approach in building my system. I first wanted to clean it out of AC and RFI/EMI noise. This was done by using Shunyata products all around (I have older line of Shunyata products), and then changed components as they started to reveal their true nature and signature. Some of components were kept, and some where changed. Now I am in phase where I am content with sound of my system, and really do not want to change anything.
Shunyata helped a lot in this quest. In reproducing realistic level of sound.
Well that is my opinion and experience so far.