question on pwr cords

Got a question for the 'power cord' experts. Is perhaps the reason that I have not been able to hear a meaningful difference in different heavy guage PC's due to the adequacy of the power supplies in my amps, pre amps, etc or is that not an issue?

Newbee,
I'll agree with Tvad, the power supply of a component won't prohibit if from being affected by it's power cord, although it does have some effect IME. I've had components with 2Kva transformers that were practically 'transparent' to sonic signatures of PC's, and mass-market stuff that only likes the cheapie PC that came in it's box.
In the very first iteration of my system, I tried a couple of PC's (TARA labs and Virtual Dynamics) and didn't hear enough of a difference to convince me I was hearing anything at all. The biggest sonic difference between that system and my current setup is the quality of the bass and mid-bass, and the quality and quantity of midrange dynamics. That early setup was pretty poor at differentiating bass notes, and most of it's dynamics were heard as upper-midrange harmonics, focused on the leading edges of notes, and weak on the follow-up. My current setup is better in all those respects, before any AC 'enhancements' are employed, and far, far, better after.

I actually recently experimented with different length power cords.

Having several Virtual Dynamics david power cords in my system I decided to let my ears determine if some longer Davids would have sonic improvments to shorter Davids.

I took the 5 foot Davids that where on my cd and amp and swapted them out with the exact same Davids (all bought and made at the same time) that where 7 foot and where on my subs.

I heard a nice improvement. The sound was more focused and better positioning of instruments when going to the 7 foot for my cd and amp from the 5 foot.

I just talked to Rick Shultz of Virtual Dynamics yesterday and told him my results. Now Rick's power cords have resonance control inside the cable and he told me that the couple extra feet added extra vibration control to the signal. I am sure theres other reasons for the change in sonic be it for better or worse, though in my system with Ricks cables it was for the better.