cable upgrades , real or rip off

I agree, it is difficult to understand a manufacturer skimping on the power cord of a $3000.00 amp. Power cords and other tweaks are still relatively new to high end audio and their impact can't always be predicted or even understood, using the rigors of applied science. Engineers, like all scientists, like to build components using sound scientific principles. Throughout history, the greatest resistence to anything new, especially if it can't be proved, comes from the scientific community. No disrespect, but IMHO the thread by Jeff_jones demonstrates that thinking.
Due to the prodding of people I trusted, and over a period of time, I tried a number of cords in different configurations with little improvement, then one day everything clicked, the improvement was unmistakable, I was hearing subtleties and even instruments I had never heard before on my cds.

Hi Studioray,
Thanks for the link. For years, before I actually invested in high end components, I read "Stereo Review" and "Audio" magazines simply because I found them fascinating (translation: I had no money). Still, I developed opinions based on, what I thought was, good old fashion horse sense. I had tremendous respect for Julian Hirsch of "Stereo Review", who claimed that all well made amplifiers sounded alike. When I finally decided to dive in, my mind was pretty much closed to tubes, interconnects and tweaks in general. I am now a firm believer in those very things, not because of measurable data, but because my system has IMO evolved musically because of them. My basic components have remained unchanged through several upgrades and changes in ancillary equipment.

Hi French_fries,
Great and tragic at the same time; great when a cable can bring you closer to the music, tragic when it costs $19k.
I've had similar experiences with Shunyata and Siltech. It wasn't until I climbed farther up the chain, than I thought would be reasonable, that I realized that exponential leap.