"Power Cords-More Recent"

”We could look at it scientifically. All the power cable needs to do is supply a constant voltage at a single frequency.”

this is the engineering view to assume that this is all that is involved (per the memorized formulas).
The scientific view would take into account repeatable observational effects that are not yet accounted for by memorized formulas and engineering dogma.

I think changing power cables provides the biggest bang for the buck (as opposed to interconnects/speaker cables) AFTER you do the fuse upgrade suggested earlier in the thread. (The QSA Light Blue fuses are amazing in terms of improvement per dollar spent everywhere I’ve tried them.)

I have a PS Audio power cord from that era and in my experience, it sounds worse than a good Chinese power cable that came with a PC that I probably bought 10 years ago, every time I’ve tried a comparison. (Try one or two that you have laying around, you never know.) I really don’t think that the amount of money spent is always equivalent with the audible benefits of any given cable in a given system.

That said, I would suggest looking at used Shunyata Research, Audioquest, or Nordost power cables of relatively recent vintage. I went with Shunyata and Nordost Frey 2 ultimately, but I use Nordost Heimdall 2 cables that are very good as well and should come close to your price objectives on the used market. I find that I like the Frey 2 with my solid state system and my low/mid-end Shunyata Viper power cables with the tube amp system. The Frey 2 helped even a $400 NAD D3020 sound really, really good with high-quality speakers that would realistically never be in the same system with that amp. (Not the normal set-up, but I was having fun when I first tried the Nordost cable and the amp was available, so…)

The nice thing is that mostly these cables seem to trade for more or less what you pay for them if you purchase them used and don’t like them in your system. The key is to only buy them with all of the original packaging and sell them the same way, because people are worried about counterfeits (and rightfully so, particularly with Nordost cables).

Fair warning: I found that I adding Frey 2 speaker cables and interconnects made everything “even more better” with my solid state equipment. Even at used prices, that can run into some $$. Ignorance may be bliss. But most importantly, have fun!

Do you have a dedicated 20 amp circuit for your listening room with hospital or better grade outlets? If not before you do or buy anything we would suggest you invest in one. Some people think power conditioners have a negative affect on there equipment it is easy to determine if that is true just listen to it with it in the system and then without it, then determine which sounds best to you. Personally we think power conditioners with surge protection is cheap insurance against your equipment getting destroyed or even better and cheaper unplug everything when you are done. As far as changing power cables, after you get a dedicated circuit installed go to used cable.com they have many selections in power cables at usually half the price of retail but more important they have a 30 day return policy. In your case you can try a cable that was originally $800.00 and if you don't like it return it or get another one to listen to, you can't beat that kind of service it is certainly better than getting stuck with thousands and thousands of dollars of cables that you or your system don't like. We think you have some pretty good cables already but there is better, the trick is finding the right one. 

Most of the power cords in my system are Cardas, Acoustic Zen, or Wireworld. At the $400-$500 range, they are almost equivalent in my system. I would recommend Wireworld from your list.

Have no experience with Audioquest or Morrow in my system, but Audioquest has sounded very good in dealer systems also.