Power Cords - Shielding or No Shielding


I have been researching power cords (PC) this past week and I must say, I find this far more frustrating than researching any other part of the audio system.

It may be a false hope, but I desire to purchase a "generic", if you will, PC that works well everywhere, I can't say now what piece of gear it will be on and even if I did, that piece may change at some point. I suspect some will say that just like other gear plan on changing as necessary; I am hoping not to do so. Anyway, I am getting off topic.

Most PC's I read about have shielding, but Audience claims on their Web site that they do not use any on their PowerChord stating, "The powerChord by audience is not shielded. We have found that shielding power cords can be sonically detrimental." More can be read here.

What is the collective thought on this?

As if the cost of interconnects and speaker cables weren't out of control (IMO), PC's are right there with them. I have already doubled the price I started out to spend and it's going up!
brianmgrarcom
Brian, welcome to the somewhat confusing world of cabling. I think much of the confusion is actually introduced by the manufacturers themselves. If you compare let's say, 10 different cables, by 10 different manufacturers, they will all have their own "proprietary" way of doing things. A lot of these "proprietary" ways are actually procedures that almost all manufacturers are using.

As you read about shielding, you must first determine the reasons said manufacturers are shielding. Some manufacturers shield for RFI/EMI rejection, some shield for field suppression (an electrical field created by a conductor passing current). And Yes, if shielding is improperly utilized, it can make for a sonically "dead" sounding cable.

There are very few manufacturers providing sensible reasoning as to why their design/manufacturing procedures work. They just simply state that they do in fact work and provide the "best sound". What the hell does that mean?

I come from an engineering background. It is very hard to sell me on how things work. I need to know why. It's a personal issue I've learned to live with. I'm going to refer you to a site that I have referred many people to. I am referring you for one reason, and one reason only. It makes sense.

This is my own personal disclaimer: I am not referring you because of any specific brand. I am referring you because the reading although somewhat brief, is quite interesting. It is probably one of the only manufacturers that cuts through some of the crap. I'm sure that there are certain manufacturers that would prefer not to have this type of information disclosed.

I hope this helps and provides some additional insight.

http://www.latinternational.com/index.php/page-10020.html

You will find that most power cords are shielded. Their are quite a few well priced cords on audiogon, diy that they will even assemble for you. If you want a cord for your cd/dvd, one of the most liked seems to be the JPS digital and if you do asearch on these you will find out why. They sell very fast when offered on the used market. If you want to step up from the diy cords that I mentioned, I think that you will find there is a big jump in price for a small gain. Be very cautious, because I see alot of mid priced cords that are made of cheap materials or not the best design, but they still charge the mid prices. Just do a search, because there are a lot of good power cords at all price levels.
Thanks Buscis2, actually, I have owned a couple LAT AC2 power cords and I have read the info Lou has posted.

Audio_profiler, I thought heavily about the JPS Digital AC, in fact I posted a wanted ad, received a reply but let it go. My reasoning was two fold, I really want a cable that will work well "anywhere" and I after reading a couple reviews on it, it seems it works VERY well on a DAC but wasn't so hot on a transport, suspecting maybe to much filtering, I believe; this left me with "questions". That said, I am sure it does do a very good job in the right circumstances.
Many cables and cable mfger's design their cables for specific application. How many times have you read that a cable worked great on a DAC, but wasn't as impressive when used on a amp or P/conditioner

Low level and digital componets would have slightly different requirements than high current (amps) and power conditioners. Low level and digital componets seem to like shielded cables that are very linear. They seem to like very stable (linear), noise free, current. Amps and P/Conditioners on the other hand are less fussy about shielding and seem to like larger gauges to bring in more current. The power supplies in Amps (if properly designed)with bipass caps or filters, and their rectifying circuts can handle the on line noise better, so may require less shielding. P/conditioner by design are supposed to be able to eliminate most on line noise. Funny thing, how many times have you read about a P/Conditioner being improved by the power cord feeding it.

Just check out some of the PC cord mfger's, Elrod has a EPS2 for low level and a EPS3 for high current, JPS has various models and some specific for digital(probably has a small shunt filter from the neutral to ground) Shunyata and CH Venhaus also make application specific cables and check out Wolff Cables who makes a different source and gain cable with a carbon shield.

One other cable mfger I would like to mention is Essential Sound Products. Their cables work equally well on source and high current (one cable fits all) and this has been commented on in a number of reviews in the past.

Do you still have that silver and black 1957 corvette???

HTH Dave
Yes, generalizing, shielding is more useful on front end components than power amps. The LAT info is a decent primer, but doesn't offer much in depth. That's ok.
There is widespread agreement that fluorocarbons' (Teflons)
very low dielectric involvement is superior for ALL cables, including AC power. Yet affordable, shielded, all-Teflon cable exists for DIY'ers or small producers. It is indeed possible to assemble yourself VERY high performance PCs for well under $75, or buy finished comparable ones from $75-$200. Above that price lies retail markup and marketing hype for questionable incremental improvement. (DISCLAIMER: I'm the mule who stocks Teflon cables to get DIY PCKits to you guys.)
Cabling is indeed system-specific, but predominantly because spectral effects result from top-octave rolling by use of different (and often cheaper) insulations...or magnetic (!) stuffers. Clever marketing of specific designs for component function type (except where total AWG gauge is correllated with current demand, or true need of shielding) is specious, at best, however. When one says that a PC sounds great on one component but not another it's more apt to be about shielding issues or a spectral effect that occurs on a particular component (audio signal carrying) vs one that doesn't (transport or tt motor), rather than that the cable is actually designed for a particular application. Why would one bother, except to purposely roll off top octave linearity, of which I abhor.
Room treatment and speaker selection are far better avenues to spectral harmony than a molassesy power cord, IMO.
Can a cable be TOO linear? Too "open", or too "black" sounding from having too wide a bandwidth or low noisefloor. Not in my book. I'm trying to debunk some myths here without personal marketing. Hope this helps a bit. Ern
Look at the news letters on the Bryston site about power cords. I have to agree, how can the last 6 or so feet provide anything after 50 or so feet of regular old wire from the breaker panel. Hell, I think we need to use gold plated contacts in the breaker panel. I have not found a single engineer that will buy into this stuff electrically unless he is in the cable making business! Once something is on the wire, it is on the wire. It's not going to filter anything out. What about all that wire to the plug? I suppose everthing is benign until the last few feet.
Sorry, but I just can't by into this stuff. If you hear an improvement, support your cable manufacturer.
Ernie, you may want to change your moniker to subaruandcableguru. A question, I have picked up some large gauge OCC power cord, about 35 feet of it. Along with 4 OCC IEC plugs.

Is there anything you recommend me wrapping the outside of this cable with, for shielding purposes or otherwise? I have noticed that when playing with some Lowther drivers, I am picking up some noise, but haven't spent enough time with it to be sure where. My goal is to make sure that the power cords are not adding any noise to my system. They will potentially be used anywhere in the system, for digital, preamp, or power amp.

Also, I have some brass plated hospital grade AC mains plugs, but they don't look to be up to the same level as the other two components, which plug do you recommend, if you would be so kind?

Thanks so much,
Joe
If you have an old house with BX wire, your power is shielded, up to the wall plug. Maybe people who like shielded power cords ought to use BX instead of Romex wire when they install dedicated lines.
Eldartford, it's nice if the shielding is NON-MAGNETIC, though...I really like the Belden 83803 over ANY BX....
Hi Joe! If you send me a foot or so of it I can better comment. RSVP personally. Re Plugs my favorite cost-effective plug is the all-black industrial Leviton that I use in my PC Kits. Its "open air" architecture has lower dielectric involvement than 52/366 or 82/315 types, and said access to BOTH sides of each terminal's screw-clamp head means you can torque down multiple leads evenly instead of squishing all the copper down on one side of the screw-heads. Truly a fine plug. OTOH I use a Hubbell 5266 and Hubbell Hospital 8315 true 20a for those who like the traditional black & white look and/or want the cache or are spec'ing a 20a IEC for a Krell or something. Cheers. Ern

How would I know if my power cable is shielded or not? It’s the stock one that came from McIntosh with my MA6900.

Just tryin’ to keep this thread alive for another decade...

Just received a response back from McIntosh that the MA6900 power cable is unshielded. In their words, "A well designed power supply will not get noise induced into the power cord..."

 In their words, "A well designed power supply will not get noise induced into the power cord..."

 

Shielding is only one aspect of a power cable.  There are improvement that has nothing to do with noise shielding.

 

 

@brianmgrarcom  Hi Brian, We all understand how confusing it all is.

Look just go out and buy a used Cardas cable, it'll get you started and you'll be able to sell it and upgrade without much trouble.

Cardas are widely compatible and will give you great SQ until you really know what you want.

Cables don't wear out nothing wrong with buying used from a reliable source.

Shielding doesn’t destroy EM radiation, it reflects it.  Same thing happens inside, a shield is going to reflect internal EM in the cable back on itself.  So like everything else in audio, you have to balance the +/- of each solution.