Double Blind Testing Prices All Power Cords Have An Effect On Audio!!!!!

[gmgraves]

On 4/13/2019 at 1:54 PM, barrows said:

I have not really sampled a lot of AC line cables, only a few, and I DIY (most of) mine.  There are so many out there, and some of course, do make some rather extravagant claims.  The Cable Company is the usual source for getting loaners to try if one does not have a brick and mortar dealer.  I have used the various models from Cardas with good results, and they are more reasonably priced than many, and made in the USA with excellent build quality and no nonsense designs.  I have also used Synergistic a little, they are very unusual, and actually have a circuit which injects some kind of noise into the cable.  I do not understand how the Synergistic stuff works, but it does work.  Perhaps the injected noise is working in a similar fashion to dither, I asked Ted Denney (owner of Synergistic) that question once, and he would neither confirm or deny it, likely just protecting his IP.  I have no doubt that the Synergistic cables often do something good, but they are a little bit too spendy for me.

Agreed on the dedicated line, if one can do it, one should certainly do this first.  Of course one can have all kinds of fun tearing out walls, not to mention deciding what wire to run as they dedicated line!

I strongly urge everyone who is reading this thread to read what Mark Waldrep (Dr. AIX) has to say about this subject. While reading it, keep in mind the old adage: "A chain is only as strong as its weakest link"

 

http://tinyurl.com/yycypm3h

[gmgraves]

13 minutes ago, barrows said:

He did not say anything, he merely re-posted a letter from a "bona-fide electrical engineer", wow, I am so impressed!

 

He did more than that! He showed how weak the “links” were both before and after that silly $2000 “boutique” mains cable. Which illustrates perfectly why such a cable can’t possibly have any effect on the downstream audio of any component that employs such a cable (except perhaps in the imagination of the purchaser of such a cable!). Now, if the rest of the mains supply was of similar quality to the boutique cable, there might be something to this mains cable nonsense - but, it isn’t.

[gmgraves]

9 hours ago, Ralf11 said:

ok, I am going to try to argue in favor of an AC power cable affecting SQ...

 

It is the closest (or first) piece of AC cable to the component in question, not just the last part of an electrical distribution chain.

But it’s not. The mains fuse in the component’s chassis and the skinny 18 gauge internal wire from the IEC connector to the power switch and to the power transformer in the component is the closest (or first)piece of AC cabling.

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As the closest AC cable to the enclosure, it picks up radiated noise (RF) and then conducts it into the component.

If there is any. Keep in mind that a component’s power transformer makes a very effective low-pass filter that has little response to RF frequencies. In other words, RF interference rarely gets transferred to the transformer’s secondary winding. That means that shielding, no matter how good, will be as effective as all that iron in the unit’s power transformer.

 

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Now, this RF noise gets past the transformer and into the circuit.  This happens either by magik, or by a parasitic leakage (via the 'ghost' circuit of capacitive coupling).

Possible but unlikely. Even were that a real world issue, There is no reason for shielded mains cable to (A) be the size of a baby’s arm, or (B) cost an arm and a leg.😊

[gmgraves]

13 hours ago, opus101 said:

 

In normal (aka differential) mode, this is true. But then you'll also have a bank of reservoir caps to help with the filtering. However its not the case for common mode, particularly if the transformer's a toroidal.

Quite true, I didn’t mention it because I thought it muddied the waters to my main point, which is that these huge and hugely expensive boutique power cords cannot possibly have any effect on the sound.

 

If all the other arguments fail to convince one of this simple fact, doubters and true believers alike should ponder this final and indisputable fact: Since the Romex* cable in one’s walls is not shielded, why would a shielded 6ft. long mains cable from the wall socket to the IEC socket on the back of a component do anything to keep out RFI? If there is RFI, it was already picked up by the wall wiring, of which there is likely hundreds of feet before the mains power ever reaches the wall outlet into which the boutique power cable has been plugged. In other words, the notion that these expensive IEC cables do anything that the cable which came with the component in question can’t or doesn’t do, is just that... a notion.

 

*Romex is the heavy-gauge sheathed, solid copper cable that carries your mains (in the USA) from your fuse/breaker box to your various outlets throughout your house.

[gmgraves]

2 hours ago, Ralf11 said:

 

 

Yes.  The only way around that is to claim that RFI sources are near the AC power cable.

Unlikely as that might be, fortunately. Perhaps the local oscillator on an FM tuner or receiver, but those are generally pretty well shielded to avoid interference in the IF  circuitry. Still, and again, there is no reason for a shielded IEC cable to cost much more than an unshielded IEC mains cable (and those are available, often for just a couple of bucks!).

[gmgraves]

23 hours ago, opus101 said:

 

Given that you do seem to accept that its CM noise which is the issue and isn't going to be much filtered by the mains trafo its just a small step to envisage a particular design of mains cable to act as a distributed common-mode choke.

I don't know if that works or not, but it is a possibility. Thanks for your input.

[gmgraves]

On 4/16/2019 at 4:20 PM, sandyk said:

 

 George

 Yet once again you plain wrong about possible audible differences between interconnects, Coax SPDIF cables and even some power cables, both for A.C. and DC too.

 I didn't believe in differences between A.C. mains cables either until  expensive Mains cables on loan from a local HiiFi dealer were  substituted between a cheap Bunnings Hardware store power board and a couple of big Nelson Pass Class A monoblocks at one of our then regular listening sessions.

 All 5 present reported hearing small but worthwhile improvements with the very expensive mains cables under NON SIGHTED conditions.

 

Alex

But, I didn't say anything about "possible audible differences between interconnects" in this thread, Alex my friend.

[gmgraves]

On 4/22/2019 at 6:05 AM, BrokeLinuxPhile said:

I could see upgrading a cord in SOME cases, surely not all though.  I've worked with some HID ballasts in the 400W range and they only include usually an 18awg cable with it.  Just not enough conductor diameter to do the job properly IMO, there is huge inrush to account for and an 18awg cord will get physically warm after a few hrs of use.  But that assembly passed UL/CE/FCC certification as designed, with the included cord.  It's a marginal pass though, barely making the cut.  Upgrade the cord and things just run safer, not necessarily performing better.

 

Shielding mattered more years ago when we dealt with CRT's, especially computer monitors.  They dumped airborne noise in audible part of spectrum and shielding would help a lot.  Emissions from modern PCs and LCDs is nothing in comparison to back in the 90's.

There is an old saying; one with more than a modicum of truth to it. To wit: “The mind sees what it wants to see.” We can expand that bit of wisdom to say “The mind also HEARS what it wants to hear!”

[gmgraves]

14 hours ago, sandyk said:

 

 That applies especially to many of the Objective members of this forum !

That’s kind of the point here, isn’t it Alex? Even though I’m not strictly an objectivist; I do all of my audio evaluation by listening. But I certainly do not expect to hear things that the laws of physics tell me are impossible, and therefore, you are right, in many cases my mind doesn’t want to hear what isn’t there and I either don’t hear it, or I ignore it as a figment of my imagination (interconnects, for instance).

 

• Bottom line here is my “ears” are my main tool for evaluating audio, but like all tools, they are limited to the tasks at which they are good. I try to keep that in mind when I use them. If my ears tell me something is going on that simply cannot be, I look deeper into the subject using other tools such as the analytical part of my brain, and where applicable, test instruments. Why just a couple of weeks ago a friend of mine brought over some ultra expensive power cord from Furutech. I explained to him how it was completely impossible for that cord to change the sound of his amplifier.    My amp had a different connector than his cord, so we used my headphone amp to test it. After letting the amp warm-up, we listened with a pair of HiFiMan EditionX v.2 headphones; first with the cord it shipped with and secondly with his new Furutech cord. He said that he “thought” he heard a slight increase in transparency with the Furutech over the stock IEC cable, but I didn’t hear anything that I could put my finger on. So I pulled out my trusty Tektronics 100 MHz Solid State ‘scope. We took the top off of the headphone amp and connected the probe across the incoming AC signal (with ‘scope AC coupled). First, we looked at the AC with the stock IEC cable and then with the expensive thick-as-a-baby’s-arm and as stiff as rigor mortis Furutech cord. With the scope sensitivity on maximum there was absolutely no difference in the look of the mains voltage with either cable. The test I made were with the headphone amp plugged directly into a wall outlet (you might recall that my mains for my stereo system goes through a massive hospital grade isolating power supply with LRC filters in both end bells of the transformer). I didn’t want the transformer “pre-cleaning” the mains between the wall outlet and the two power cords. I was interested in seeing what the Furutech cord could do to improve mains quality (after all, that’s the only thing a power cord could possibly do to “improve” the sound of an audio component). After this test showed absolutely no difference between the AC current through either cable (and just as I predicted), my friend returned the Furutech cable for a refund. I suspect that he will think twice in the future about buying “snake oil” audio products! Of course, YMMV, but I doubt it. 😉

 

 

 

 

[gmgraves]

3 hours ago, Allan F said:

 

And, of course, you reject out of hand the possibility that what you "ignore as a figment of my imagination" is, in fact, real. Your bias, IMO, stems from the assumption that any audible differences that can be heard must necessarily be measurable with current knowledge, technology and techniques.

It’s not an assumption. It’s really quite simple. There is no way that something like a coaxial interconnect, for instance, can affect an audio signal, as low a frequency that it is without affecting signals - some of which could be life and death critical at higher frequencies. In which case they would have been studied and the reason for the anomalies would have long sense been found and either corrected or compensated for. That’s only common sense. 

 

 

 

 

 

[gmgraves]

41 minutes ago, mansr said:

As a lifelong misogynist, I’d say that somebody has hit the nail squarely on the head!

As a wise man once stated: “If they didn’t have p*******, we would hunt them down and kill them!” Fortunately for them and us guys, they do.

[gmgraves]

2 minutes ago, sandyk said:

 

 That may be your personal reality George, but it isn't the personal reality of many other people.

These days the equipment is usually way more revealing than back then.

 You only need to look at many older TV series compared with recent TV  series , or look at Music DVDs from the 80s and 90s compared even with modern .mp4 LOW Bit Rate YouTube videos

Alex, don't you find it increasingly difficult to buck physics and electronics reality? It doesn't matter how "revealing" equipment has become. If anomalies in the physics of conductors, other than the characteristics we already know were ever found; weather it was yesterday of 50 years ago, do you not think that those anomalies would have studied to see whether or not they were capable of causing errors in mission or life critical applications? In my humble opinion, it is naive (or arrogant) in the extreme to believe that some "unknown anomalies" would only affect a lowly audio signal and not affect anything in MegaHertz range and therefor possibly pose a potential danger in critical systems. If such anomalies had been found, don't you think that universities and government laboratories would have spent millions examining modern conductive materials at the molecular and even atomic levels to find out what is causing such anomalies? 

I'd be willing to bet money that in the real world of electronics, that my "personal reality", in this case,  is much more mainstream than yours! 😉

[gmgraves]

7 minutes ago, Allan F said:

 

A classical case of the the logical fallacy that is correctly called 'begging the question'. You assume as a given the point that is in issue.  IMO, it is not common sense to rely on "what would have been". By that reasoning, for a very long time it was common sense that the sun revolved around the earth. That is, until Copernicus came along.

It is not a logical fallacy. My point is that if such an anomaly in conductors were found in mission critical applications, that anomaly would have been studied. That it hasn't (as far as I know), says that this anomaly has not been noticed and that there have been no incidents (that I know of, and I've searched extensively) that would bring such a an anomaly to light in the mainstream technological world.

[gmgraves]

1 minute ago, sandyk said:

 George

My BR comparison discs show that some "unknown anomaly" does just that .

 This anomaly affects both Digital Audio and Video.

 

Alex

I like the way you and Alan F ignored the bulk of my post outlining the experiment which showed that there is absolutely no difference between the mains transmitted through a garden-variety IEC cable and an expensive Furutech DPS-4.1 cable. I wasn't discussing interconnects or USB cables, just these nonsense boutique mains cables.

[gmgraves]

10 minutes ago, sandyk said:

 George

My BR comparison discs show that some "unknown anomaly" does just that .

 This anomaly affects both Digital Audio and Video.

 

Alex

Interesting, but irrelevant. We are talking about  boutique mains cables. I know nothing about anomalies in digital audio and can't comment on them,  and I couldn't care less about video. So,  I have no beef with you on those accounts.

[gmgraves]

1 hour ago, sandyk said:

 George

 We will both undoubtedly keep ignoring them as there is nothing in them that we haven't seen from you before, and disagreed with too.

I repeat that it was being unfair to test them using a low current device such as a headphone amplifier, instead of the much higher current devices they are designed to work with .

 

Alexi

Well, denial isn’t just a river in Africa, as they say. Unless the power amp in question is pulling close to the rated mains maximum, the size of the amp is irrelevant. No noise on the line (and no RFI) means no noise or RFI on the line. So there is nothing for the boutique mains cable to do, assuming that at its short length, it can do anything (which is a huge assumption). So your retort about the headphone amp being “a low current device” has no meaning in this context.

[gmgraves]

1 hour ago, Allan F said:

 

Can you at least try to spell my name correctly, Gorge.

sorry, it was a typo, not an attempt at an insult (which I would never do purposely).

[gmgraves]

1 minute ago, BrokeLinuxPhile said:

If there was noticeable variance between source files and destination files while copying, this would have been seen in other industries.  I would have a very hard time believing this is isolated SOLELY to video and audio.  Court and other legal docs could not be trusted, financial transactions would be invalid, it would be chaos.  That's not bias but evidence.

You are of course, quite correct. 

[gmgraves]

1 minute ago, Allan F said:

 

To the many who have heard the clearly and repeatedly identifiable audible differences that power cables can make, your denials are completely meaningless.

I wouldn’t call something that is not quantifiable or even measurable and is in the middle of a circuit that has weak links on either end of it, (the mains wiring in the wall, and the tiny wires going from the IEC connector inside the audio component, not to mention the tiny fuse conductor in the line between the mains input and the primary of the transformer) meaningless. Only neurotic audiophiles would ignore the reality of the facts, and continue to insist that their imaginations are telling them the truth.

[gmgraves]

 

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If you can hear a difference, that difference can be easily measured by a skilled person using the correct modern test equipment.

Unless, of course, that “difference” is being imagined by the listener as in confirmation or expectational bias. in which case it cannot be measured for the simple reason that said differences do not really exist.

[gmgraves]

7 minutes ago, Paul R said:

 

Like IMD for example? Everyone heard it but it did not exist? Until of course, it did?

 

There are hundreds of listening tests reported even just in CA George. USB cable differences are about as real as anything can be.  

 

Unfortunately, there are also reports about power cables, and differences in formats, and even differences caused by different RAM in servers. Some of these reports are without a doubt, the result of wishful listening. 

 

But certainly not all of them. Engineering minds tend to want to dismiss the lot, but that would be a mistake. 

I don’t dismiss the lot. For instance, speaker cables can really make a difference, but there is a real reason for that. Amplifiers and speakers interact far more than say the output of a DAC and the input of an amp or preamp, which just need to be connected together by a reasonable length of coax. Although RG-59 has the closest impedance match, in the half-meter to 2 meter lengths commonly used in a domestic audio set-up, it’s not all that critical. 

But speaker cable (depending on the run length) can be critical to proper speaker performance. Some speakers are very cable sensitive and others (like Magnepans) don’t give a damn. 14 Ga zip cord is as good as a $10,000 run of MIT as far as they are concerned, but mY Martin Logan’s are somewhat cable sensitive. This is because the wire run becomes part of the impedance profile of the speaker an Hereford is part of the load the amp sees.

on the other hand, interconnect sound and especially mains cable sound is just nonsense with absolutely no since behind it.