Power Cords


I currently have Wireworld Silver Electra power cords with upgraded Platinum plugs. I had two 1M Wireworld Platinum power cords, but rearranged my system and required longer cords. Yesterday I borrowed two Shunyata Sigma NR power cords. On the first note my wife softly said, "that sounds better". She said it was clearer. I listened for a couple hours, changing the power cords a couple of times. In my system and to my ears this is my conclusion:
The Sigma's are cleaner, definitely has more bass, a dead silent and completely black background. The Wireworld cords are more detailed, with a wider soundstage and better spacing/separation of instruments. All things considered I'll keep my Wireworld, but I'm curious to listen to other power cords.
After inserting the Sigma's I just don't understand how anyone that listened to different power cords could conclude that they can't hear a difference. There is a difference, but like any other component the individual has to decide if the change is worth it. $6K for two power cords is relatively expensive. Expensive, but oddly maybe a good value? In my system there was a definite improvement with better bass impact and articulation. Would spending $6K or just changing amplifiers yield similar results? As with most components there are trade-offs...is there a power cord out there that has the benefits of the Sigma's and Wireworld Silver Electra's? If so, at what cost?  
ricred1
Breaking News! This just in! I must be a Mind Reader! Audioquest controls wire directionality for its power cords. From the Audioquest Hurricane power cord web page:

"Dielectric-Bias System (DBS; US Pat #7,126,055): By creating a constant dielectric field for the cable’s primary capacitance field or dielectric, DBS assures extended bandwidth and more evenly filtered noise dissipation, eliminating the distortions and ringing that plague other cables even after years of use and so called “run-in time.” In addition, DBS assures that the RF Noise-Dissipation System works as linearly as possible.

Controlled for Correct Directionality: All drawn metal strands or conductors have a non-symmetrical, and therefore directional, grain structure. AudioQuest controls the resulting RF impedance variation so that noise is drained away from where it will cause distortion."

Cheers

I just phoned with AQ about the plugs. From the Hurricane and above they use Silver plated (over pure red copper) plugs.

I don’t like the shape and shiny new DBS of AQ. But they say it is an improvement over the old one. They improved the isolation compared to the older ones.
I second the previous comment about Signal Cable power cables. I've owned 4-5 of these, from top to bottom of the line--all sound great & are built like tanks.

Mine is a very good desktop system, not a full-blown audiophile system in living room, so maybe I'm missing something. But I've been more than satisfied w/everything I get from Signal Cable (that includes 1/2 a dozen interconnects, all excellent).
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.
Definately consider the Acoustic Zen line. I have used so many PC's over the years and finally settled on the Acoustic Zen Absolute cords. A bit pricey but well worth the $$$'s