Speaker Cable Upgrade... Advice Please

I forgot to say that I am retired and living in Boulder Colorado and that if anyone nearby wants to check out my speaker wire "system" that they are welcome to give me a call at (720 550-6908 anytime to check it out.  I live in a very easy to get to location so it is very easy to visit me.  I have no financial or other connections to either Jenna Labs or MG Audio Design whatsoever.  I can not make any money or profit.  Just pasing on my observations.  It is obvious to me that both manufacturers offer products top in their lines.  It is just by chance that I discovered how well they work together.

In regards to PCs making a difference. I came across a screaming deal on 3  Valhalla PCs, 2 meters for $500 each.I also bought Valhalla 4 meter Speaker cables for $900. The speaker cables were in rough shape. I sent them back for repairs. 2 weeks later I received the Speaker wires back and recertified. $620 charge. While the speaker cables were in repair, I put the PCs into the system. 0ne into my preamp the other 2 into my mono blocks. Wow was I amazed. A veil had been lifted. The music is more detailed while being very relaxed. As a point of reference I was using Analysis Plus prior. Never thought I'd see that type of change. As a side note I'd never spend the MSRP on the Nordost cables.

I agree that a power cord might be the best way to go first.....perhaps stick with Cardas and pick up an older Golden Reference.  Other possibilities would be a Shunyata NR or maybe Transparent.