[CE]

PTFE insulation is for a specific purpose...mostly high temp conditions., corosive enviorments.  NOT audio performance.  somewher along the line, some marketing genius, decided, hmmmm, we can sell this stuff to nudnicks convince them of it's audio abilitys..and make money.  The only way an improvement is accomplished by changing a wiring device, would be if the one it replaced was so worn out, loose in holding the cord cap...in which place it was a fire hazzard more than anything.  A replacement one holds the plug as it should.  A $1 residental grade accomplishes that. There is no sound improvement in using a spec grade or hospital grade device.  As to the bogus claims of the "audio grade" wall device marketed by marketing types, it's all nonsense.  NEMA has no such designation.  Where is the FTC?  To claim anybody can hear a difference in a Hubbell, Leviton, or Pass and Seymour device is such lunacy, beyond comphrension. As nutty as hearing a difference in a AC cord. Did you also replace the ckt breaker in the service panel?  If not, why not?  It's in the same path of the magic electrons.  Check the wire going to the street transformer...see if it meets audio specs.  In BIZZARO world, anything is possible.

[JohnR]

PTFE has a lower dielectric constant than PVC (for instance). It's also constant with frequency, unlike PVC.

[Jay S]

CE.

Help me to understand...  

For outlets do you mean that they all have the same contact pressure, contact resistance, etc.?  Or do you mean that these differences have no impact on audio equipment?  Is a $3 P&S 5242 no different from a $0.50 generic outlet?  

Getting back to power cords, there are lots of variables in power cord design.

-- Conductor thickness (e.g. 14 gauge, 12 gauge, 10 gauge, 8 gauge, etc)
-- Conductor material (e.g. bare copper, enameled copper, tinned copper, silver plated copper, copper allows, nickel plated copper, silver plated copper clad steel, copper clad steel, tinned steel, bare steel)
-- Inner conductor insulation (e.g. foamed teflon, solid teflon, foamed polypropylene, solid polypropylene, foamed polyethylene, solid Polyethylene, rubber, pvc, polyurethane)
-- Shield (e.g. none, foil, copper braid)
-- Connectors
-- Quality/integrity of crimping/soldering of conductor to connectors

Do none of these variables make a difference, even in terms of measured scientific performance?  If not, why is it that you buy such a wide variety of cable from a company like Belden?  Is it just for the high end audio market?  

Notice that no one is talking about audio grade.  I don't care to justify a $1,000 price on a 3 foot power cable.  I do believe that there are real differences in audio cable.  I also believe that these differences do affect the sound quality of audio equipment (the price is a totally separate matter).

[CE]

PTFE has a lower dielectric constant than PVC (for instance). It's also constant with frequency, unlike PVC.

Nothing to due with audio frequencys.  This is not RF, high temp etc.  Is your system in a highly corosive enviorment.

[CE]

Contact pressue is relative to harsh enviorments.  When the yanking out of a cord would happen, in say a hospital, on life suport equipment.  The standard UL listed. residental devices meet UL listing requirement for the enviorment they are used in. The hospital grade have nylon face, not for any electrical performance, but to stand up to the enviorment, as in cleaning with harsh solutions etc. That may spalsh on them.  NEMA, what a concept. devices for a specific purpose.  teh contact resistnace between a commercial device and residential device has about as much effect on sound as the position of the sun during the day  Why doesn't the contact pressure of the wires terminated int the ckt panel have any effect?  It will have an effect even on your tv, if your terminations are loose or corroded from years pf use.  In which case, it's a FIRE hazzard and needs to be repaired. If you think it matters, why yse straight blade wiring devices, switch to twist lock...even more secure.  OH, the bend in the wiring device has a negative effect on the sound?  If contact pressure has an effect on sound, why do nudnicks replace hard wire power cords with removable IEC types.  you just created ANOTHER contact point..and IEC plug in, are pretty insecure.

[CE]

they make wire for specific functions, freqs., enviorments. Why would a 14 ga. cable make a CD player sound better than the fuly functional, within ampactiy, make it sound better? a CD play is barley a 1A load.  A 10 guage line cord which is capible of 30 A, for a product that is a load of 1 A or less?  Why not replace the line cord on your TV?  Shouldn't it improve it's performance?

[JohnR]

Belden seems to think that the dielectric constant of PVC varies in the audio band:

http://bwcecom.belden.com/college/Techpprs/ciocahalf.htm

Also, I think it's about time you stopped insulting people. Leave out the name-calling from now on.

Thanks,

JohnR

[Jay S]

teh contact resistnace between a commercial device and residential device has about as much effect on sound as the position of the sun during the day  

If contact pressure has an effect on sound, why do nudnicks replace hard wire power cords with removable IEC types.  you just created ANOTHER contact point..and IEC plug in, are pretty insecure.

Contact resistance and wire resistance affect the ability of a component to instantaneously draw current to recharge its power supply caps.  

And, yes, I agree that the best connector is no connector.  All things being equal, if you can remove an IEC and hard wire a cable, so much the better.  However, a crappy hard wired cord is not necessarily better than a quality cord attached using an IEC.

[Jay S]

they make wire for specific functions, freqs., enviorments. Why would a 14 ga. cable make a CD player sound better than the fuly functional, within ampactiy, make it sound better? a CD play is barley a 1A load.  A 10 guage line cord which is capible of 30 A, for a product that is a load of 1 A or less?  Why not replace the line cord on your TV?  Shouldn't it improve it's performance?

You need to consider instantaneous as well as constant/average current requirements.  Wire gauge plus contact resistance can be analyzed to calculate voltage drop.  Thickness/gauge may not be too important beyond a point for a low current device like a cd player.  But the quality of the shielding of the power cord can be important to protect against RFI being radiated by the power cords of adjacent audio gear.  

As for the TV, just because they come with crappy power cords doesn't mean that they couldn't be improved on.  TVs use even more power than cd players.  And maybe the eye is more sensitive than the ear.

[ehider]

Well CE is on a roll here. I have to say that many years ago I would have completely backed up his logic. CE's arguments make quite a bit of sense. As an electrical engineer myself, I can present hundreds of sound arguments to why these things cannot make a sonic difference. (Sometimes knowledge is not what it seems   )

Like CE, many years ago I too presented the same exact "logical" arguments such as "why not have the power company run your special wiring all the way back to the power generator?". That argument is very sound, but indeed wrong .

Buuuuuuuuuuuuuuuuuuuut, here's the rub: Power cables, wire choices, outlet choices and insulation DO make an audible difference in a high end system ! I know, I've spent the last 5 years making my own cables and have found significant differences in materials, etc  (I now don't let my degree get in the way of my education )

The problem with the above aforementioned snake oil type of argument is that there are tens of thousands of audiophiles who swear they have heard the differences in power cables, dedicated lines, insulation choices and even outlets! Those audiophiles have backed up their experience with over a million dollars in total for these types of tweaks! Additionally, every high end reviewer (over 120+) is in complete agreement with these sonic improvments by virtue that they too have heard the differneces! (except one sole idiot - Peter Azcel, who has "proven" that all good amplifiers sound identical - perhaps he is related to the late Julian Hirsch of the old rag Stereo Review, who "proved" that all cd players sound the same in a "Scientific Test"  ).

  CE, you've got to ask yourself some questions here:

 How can over 75+ cable companies can sell thousands of power cords each and every month to audiophiles if these cables don't make a difference  

Why are so many audiophiles "upgrading" and spending upwards of $500 on power cords alone  

Is everybody deaf and just hearing things, even in double blind verifiable comparisons  

Is the world filled with nothing but snake oil cable companies who are are in a grand conspiracy to sell us expensive cables and other power accesories that don't make a differnce  All of them are crooked Can you really buy this concept

Why are there thousands of postings on Audio Asylum and Audiogon about cables, comparisions, outlets along with material selections for DIY cables too  Is everyone off their rocker  (Those forums have the bulk of the most veteran audiophiles in the world today )

BTW: I DO beleive that there ARE companies that DO rip people off with B.S. type of audiophile products, but these are NOT the norm in my experience. Those companies typically do not last very long. The competition is too stiff and the internet is too powerfull of an information source. Indeed, audiophiles use their ears a hell of a lot more than Bose owners!

  One last important thing to note: I've been to more than a few "audiophiles" houses to find that their set-up is not capable of producing the soundstage cues, ambience decay or ultimate resolution to fully appreciate the differences between cables, outlets and alike. Indeed, my original system from my college days (Hafler amp,pre-amp and Polk's top speakers) is still owned by one of my buddies. A year ago we fooled around with his power cables and outlets trying to tweak it and the differences were NOT audible  !!!!!! Of course his system is far from perfect, but we were both shocked as we tried to add some power tweaks to his system only to discover that the resolution of his system was inadequate to show these differences .

[CE]

So when the piece of wire doesn't change anything, it's because of some other component?  WOW, you must be a politician.  Do my Legacy Focus speakers in bi-amp mode with 2 VanAlstine DH500 Hafler rebuilds allow enough resolution?  Omega III AVA preamp, SACD Philips 963...SoundKing 12ga speaker wire? Line cords have no sound....a line cord needs proper ampactiy for the load it's connected to.  That's all there is too it.  Since it's not high abuse enviorement, no SOW, SJT SOWW  outer  needed.  NEMA, what a concept!!! Electrical products for a function.

[Jay S]

So then resistance is irrelevant?  Every and all cables with the same current rating will be just as good?

[ehider]

Now, now CE. Let's not get testy. I too like you had the same EXACT arguments! My "knowledge" and engineering background put me in the same exact mindset as you are in today! Thankfully, I learned to use my ears and not my "learned education". I was hoping that my thread may potentially open your mind to a possibility that some things improve the sound even if we cannot justifyably make "electrical sense" of them.

As I put together that thread I tried to think what may have swayed me way back when I thought like exactly you. The problem was that I would not even try some of the ideas or cable designs because I just knew that it was illogical, snake oil ballyhoo! With my similar "engineering know how" past stubborness in mind, I did my best to "open your mind to new ideas that don't make elelctrical sense". Perhaps I need to work on my delivery here?

In terms of your equipment, I was not trying to dis it or make you feel as if your system could not show these differences. My point was that there are systems that will not readily show the differences between power cords and outlets. Sometimes audiophiles who proclaim they cannot hear any of the differences are really just limited by their system. Weather or not your system does this was not my point.

BTW: Did you really consider the questions that I posed to you? Could thousands of hard core audiophiles with experience beyond you and I all be wrong? Are all of the manufacturers making money on hype alone? (We are talking about 70+ companies here). Is this all a grand conspiracy? What about the double blind comparisions with 90%+ statistical results? Are those tests a conspiracy also? Of course I could be part of the grand conspiracy too, so perhaps I need to look in the mirror?

In a nutshell, the ears don't lie. Please please please don't let your "knowledge" get in the way of your education!

[Jay S]

While I am happy to buy audio gear based on what I hear, I also really like the approach that audioengineer takes, using science to get a better understanding of how measured performance of cables impacts on their performance in audio systems.  

Here's a good data-driven explanation of the age old question of....

How does 6 feet of low-inductance cord make a difference when
there is 25 feet of ROMEX in the wall?
A typical 6-foot 14 AWG rubber cord and 25 feet of ROMEX has
inductance of 7.2 uH and resistance of 235 mohms, ignoring the plug
resistance effect. Therefore, the voltage drop at 20kHz will be:
I(wL+R)= I(.905+.235) = I(1.14). With a 6-foot [XXX power cord] and 25 feet of ROMEX, the inductance is 5.9 uH and the total resistance is
147 mohms. This is an 18% reduction in inductance and a 37%
reduction in resistance. The voltage drop for this combination will be
I(wL+R) = I(.741+.147) = I(.888). So at a fixed dynamic current I, the
voltage drop in the entire power feed at 20kHz is 22% smaller with a
[XXX power cord]. The reality is even more compelling. When you
add in lower plug and receptacle resistance and the fact that the di/dt
on the power cord will have spectra well above 20kHz with some
amplifiers, the low-inductance cord makes an even bigger difference.

Notice that the voltage drop is calculated for a fixed I (current).  This indicates that there is more to power cables than just their current rating!  
Even if you do not agree that voltage drop has any impact on sound quality, I find this explanation much more intellectually stimulating and factual than cryptic references to "speed of light circuits" or "magic dust."  

To be fair, while measurements are objective, they may not be measuring the right things.  The question then becomes, what do we measure?  If we are unable to find measurements that correlate with what we hear then we just have to make a decision without having the crutch of science to lean on.

[CE]

So then resistance is irrelevant?  Every and all cables with the same current rating will be just as good?

yEAH, THAT'S ABOUT THE SIZE OF IT.  tHAT IS HOW THE AMAPACITY IS RATED.Then enviorment used in would determine the cord type..SOW SJT, SOWW...dozens of cord types.  Nothing rated in audio quality though. How bout the nonsene of "strand jumping" some marketing BS type made up.  Why are studio mics wires with nice flexible stranded wire?     some bat eared wizzards claim to hear the difference between solid wire and stranded wire!!!!! That is a remarkable abilty. Have you froze any receptacles lately?

[CE]

While I am happy to buy audio gear based on what I hear, I also really like the approach that audioengineer takes, using science to get a better understanding of how measured performance of cables impacts on their performance in audio systems.  

Here's a good data-driven explanation of the age old question of....

How does 6 feet of low-inductance cord make a difference when
there is 25 feet of ROMEX in the wall?
A typical 6-foot 14 AWG rubber cord and 25 feet of ROMEX has
inductance of 7.2 uH and resistance of 235 mohms, ignoring the plug
resistance effect. Therefore, the voltage drop at 20kHz will be:
I(wL+R)= I(.905+.235) = I(1.14). With a 6-foot [XXX power cord] and 25 feet of ROMEX, the inductance is 5.9 uH and the total resistance is
147 mohms. This is an 18% reduction in inductance and a 37%
reduction in resistance. The voltage drop for this combination will be
I(wL+R) = I(.741+.147) = I(.888). So at a fixed dynamic current I, the
voltage drop in the entire power feed at 20kHz is 22% smaller with a
[XXX power cord]. The reality is even more compelling. When you
add in lower plug and receptacle resistance and the fact that the di/dt
on the power cord will have spectra well above 20kHz with some
amplifiers, the low-inductance cord makes an even bigger difference.

Notice that the voltage drop is calculated for a fixed I (current).  This indicates that there is more to power cables than just their current rating!  
Even if you do not agree that voltage drop has any impact on sound quality, I find this explanation much more intellectually stimulating and factual than cryptic references to "speed of light circuits" or "magic dust."  

To be fair, while measurements are objective, they may not be measuring the right things.  The question then becomes, what do we measure?  If we are unable to find measurements that correlate with what we hear then we just have to make a decision without having the crutch of science to lean on.

20Khz on a power cord.  What kind of AC line do you have?  Mine is 60Hz.  Voltage drop so what?  A properly designed amp/pre amp can deal with it a few volts ...do you think .1 OHM or so of negible resistance in a wall outlet to cord cap, is gonna effect the sound of an amp...you are reading too many cool ads.   You just don't get it.

[Marbles]

I don't get it because I have heard differences in power cables on my amps, but can not explain it.

I use the 12 ga speaker king speaker cable (from Parts express) you use on my surrounds in my HT.  I don't use them for my fornt 2 speakers because I have found much more revealing speaker cable.

Maybe if you upgraded your speaker cable you could hear differences too, or maybe you just are not able to hear differences......

[Jay S]

you are reading too many cool ads.   You just don't get it.

CE,

I give up discussing with you.  I don't find you helpful nor open to considering new ideas.  Why do you even bother being on audiocircle?

[nathanm]

Sorry, don't mean to sidetrack the discussion, but I just have one question; is ampacity\amapacity a real word?

P.S. CE - take a few seconds and learn to properly code your quoted text.  It's not really all that difficult and makes your posts easier to read.  Thanks!

[ehider]

C.E. just doesn't care to "measure" the other audiophiles opinions here IMHO. He's got his math and formulas, therefore HE is right regardelss of what we hear!

What's worse is that C.C. ends up the big loser by not allowing others to give him valuable advice and experience!

 I'm sooooo glad I didn't stay in the mindset that you are in C.E. You definately need to realize that there's a thing called "thinking outside of the box". Ever hear of that one?