Power cable Advice...

If you have all the money that you want/need, go ahead and blow whatever you want on power cables.  But it doesn't seem that you are in that category.  I have a Pass 250.8, ARC REF 6 and Sabrina X speakers.  In my system, I have heard a decent, audible improvement in the bass when switching from stock to an upscale PC.  By no means is it a "blow me away" difference, but it was certainly an improvement.  Is the minor improvement worth $5k, 10K or more?  Certainly not to me.  I have had Morrow MAP 3 PC's, Audience PowerChords and ultimately, Shunyata Alpha v.1 and V.2.  The difference between Stock and the Audience cables was noticeable.  The difference between the Audience and Shunyata (on my MSB DAC and Pass amp) was not, or barely.  An Audience on my REL s/510 v. stock was not noticeable at all.  The biggest difference that I noticed was replacing the ARC stock PC with a Shunyata Alpha v.2, which was a noticeable improvement.  My advice: don't buy into the hype. Purchase used, and stick to the <$1500 used market.  I'm sure that, depending on your system, there may be a difference between the Shunyata Alpha's and Sigma's for example, but whether that minor difference is worth the $$$$ is a judgment call only you can make.  I highly recommend the Shunyata Alpha's and a sweet spot in the used PC market.  I'm very happy with them.