question on pwr cords

Unsound, your question isn't quite clear to me. All three conductors in a power cord are connected to the plug at each end. One to hot, one to neutral and one to ground. If, in addition, the cord has a shield (usually a metal "braided tube" right under the outer jacket and surrounding the three conductors) it will capture any stray RFI in the air and drain "it" to ground, by connecting the shield to the ground pin of the AC plug.

As long as the shield is ONLY connected at ONE END (the ground pin of the AC plug) it cannot conduct any current (like from one end of the cord to the other.) If however, it's connected to the ground pin of the IEC plug as well, then you have two separate but connected "wires" (the shield-wire, and the ground conductor-wire) connected together at each end of the PC. If you draw a diagram of this, it's what's called (in circuit terminology) a loop -- in this case a "ground" loop. It can then act as an antenna that will pick up electromagnetic radiation (mostly 60 cycle AC from the cord itself, or other nearby sources of AC) and you get devilish hum.

Some PCs (like Cardas for instance) employ a double floating shield. There are two concentric shields (insulated from each other) and one is connected to the AC plug ground pin (only), and the other is connected to the IEC ground pin (only) and I guess that's about as good as it gets ;--)
.

Blakeaudio,

I can hear the difference between a 1.5 and 2 meter power cable of the same type, and so can you, if you'd try it.

Also Nsgarch, not all CDP's and DACS sound better with 10awg or heavier PC's. Some, maybe even most, do, but not all. A friend has a modded Sony SACD player that sounds best with 11-12 awg PC's. I've also owned some DSP units that only sounded 'right' with their original PC's, which were only 16 awg. Why? I wish I knew for sure. :)

I am looking at about 9ft required (from current 3ft) as a reuslt of set chg so I guess that length expansion in itself will not be an issue.

On the unobtrusive....I have heard the Crystal Ultra interconnects and despite being very thin, they sound very impressive indeed...guess pwr cords are different? Did notice the do produce a thinnish looking pwr cord which they term reference so was interested...aslo aren't Nordost's Valahalla pwr cords less obstrusive than the norm? Also, Jena labs cable?

I currently use Shunyata, and I do like them but they are big pythons that are creating a bit of WAF issues...

Tplavas,

I have to say that I'm amazed at your aural accuity! Just how does the difference that you can detect between a 1.5 and a 2 meter PC of ths same brand and construction manifest itself? What is it that you hear that is different? Do you think that this observation is universal, that is it applies to all amps, or just yours?

I'm facinated.

Newbee:
That's an easy one, the 2m PC gets you 0.5m closer to the music....
sorry couldn't resist..