2. cables
  3. 170199-100084

Power Cord Shielding

There has been tons of discussions regarding power cords. For me, shielding is the most important factor.
Thus preventing AC noise emitting from the power cable which may interfere with the signals of other cabling in your system.

I have had some fairly expensive cables from the likes of Black Sand and Cullen, that when I ran a handheld AC voltage detector along its length, whilst plugged in, the line detector would light up. As for cables like Pangea and even some stock, manufacturer’s cables (Coda, Wyred 4 Sound) I get no readings from the voltage detector.

That said, I’m surprised to see how many amps have the IEC connection on the far right or for left on their units, right beside the speaker binding posts. I think in the middle of the amp, as far away from any connections would be best. Such as the Luxman 505uXII or the Coda CSiB.

What are our thoughts?




high-amp
holmz's avatar
holmz
2,328 posts
 
  • When you turn it up all the way do you hear 60 Hz humming noises?
  • Or some harmonic of 60 Hz?
  • Or what is the frequency of the noise on the AC line that needs to be addressed with the shielding?
  • Are you concerned with voltage leaking out or magnetic fields?

A few preamps have outboard power supplies and these feed DC to the main part of the preamp. But power amps, do not have the gain of a preamp.
high-amp OP
508 posts
 
None of the above. It seems by the first two responses, my concerns have been negated. Thank you
tantejuut
125 posts
 
Shielding on power cords is not always a good option. It can induce eddy currents, a pathway for leakage currents, limit the bandwidth, make the earth wire noisier and create resonance. I also can kill the boogie factor because it messes up the subtle timing of transients. 

The advantages are less EMI/RFI pickup and radiation of the cable itself. I only use shielded power cable on my TV and Computer. Power amp & DAC are not shielded. If you go shielded, use shielded connectors or connectors with a carbon shell at least.




high-amp OP
508 posts
 
Interesting, learning lots, glad I brought this up!
holmz's avatar
holmz
2,328 posts
 
Oldhvymec brought up weaves and routing.

When the current is high like a power amp, then the magnetic fields are high, and his suggestions are sage.

And it is hard to shield against magnetic fields.
More to discover