Power Cable Test – Volunteers Needed

SSB - against all my instincts to do so I must admit you are exactly right. Noone contests cartridges or speakers sound different or invokes double blind tests to see if they do. Consequently the effect is so tiny for cables that the effects very existence MUST be in contention, hence the need for all this. If the difference is so stark then everyone even in a small test will produce a set of unequivocable results - just as if you put a bag over the speakers. This logic about cables also applies to record clamps, mana, peter belt devices and the tooth fairy.

 

On the other hand, there may well be a significant 'green eggs & ham' syndrome where people don't find out whether there's a difference - significant or otherwise - on the grounds that "it's obvious that it can't make a difference, therefore I won't listen".

 

3DSonics wrote:

meaningless adj. without meaning

The test results are not meaningless. In your opinion they are.

Others can derive whatever level of meaning they wish from the test results as I've said from the beginning.

There is very little information that should “definitely be censured†much less the results of hi-fi testing of one sort or another. Disputed by all means.

You mentioned earlier you viewed the results with a “certain sadnessâ€Â. This type of suggestion is far more regrettable and indeed deserving of sadness.

The test system comprised:

Arcam FMJ CD23 CD Player
Bel Canto Evo 2i Amplifier
Meadowlark Osprey Loudspeakers

For the sake of brevity I'll re-post the summation of conclusions by Meninblack as this is still the most considered I've seen.

I'll put you down as a number two Thorsten.


1. The cables made essentially no difference.
Fits the facts. The only counter-evidence is Mr. C's assertion that differences were plain to him. Tony, were you sighted or unsighted of the cables? If unsighted, did you correctly identify the kettle lead every time?

2. The cables made a difference, but it was so slight that the resolving power of the experiment was inadequate.
Possible, but with three blind testers and only one variable each time this would imply that the differences were very slight indeed. Very, very slight in fact.

3. The results were somehow fiddled by the panel or the experimenter.
Paranoid nonsense!

4. The panel's hearing is inadequate. The differences are like night and day, but only to the platinum-eared elect.
What, we've randomly ended up with three keen audiophiles and cable believers who just happen to be deaf? Unlikely.

5. Some other unidentified factor prevented the differences from being heard.
Always a good get-out! Anyway, Tony heard them. Why not the other three.

http://www.hifiwigwam.com/forum1/1104-2.html


As for amusement, fear not Thorsten. Your various audiophile warblings have been a reliable source of amusement to me so consider the favour returned. Chinese chess pieces super-glued to CD players and the like .. very amusing

 

Not hugely likely. The differences are either readily apparent, or quite subtle. If the former, sceptics would be a discredited minority, and their refusal to listen would be an obvious ruse. As it is, the only people who believe in the audibility of power leads are a small number of audiophiles. Which suggests the smart money is on the differences being subtle.*

-- Ian

* IMO so subtle that they're almost certainly only in an individual's head, but that's just me

 

Ian, I suspect the differences are somewhat exaggerated, although I do believe they exist. 13 out of 15 identified this. Personal subjective preference has no place in an objective test surely?

What do you think of the people who cannot hear a the differences betweeen vinyl and CD?

 

Sadly, 2 out of 3 testers also identified a difference even when the cables weren't changed, although, as has been said, this control test would need to be repeated more often for its statistical significance to be more clear. Likewise, the testers were not tested in their ability to repeatedly identify a difference, so we can't conclude whether the testers were simply predisposed to say they heard a difference, or really did hear a difference. In any event, the test, flawed as it is, gives no support to the proposition that power cables make a significant difference, and are entirely consistent with the proposition that power cables make no significant difference, which is what everybody outside a small group of audiophiles believes to be the case.

Anyway, not using posh kettle leads makes one feel so much purer, as well as richer. if you can give up smoking you can give up snake oil.

-- Ian

 

Even if you accept that,then the debate moves to whether 'different' equates to 'better',which is unprovable.The only acceptable meaning for 'better' in this context would be 'more accurate' to the original recording,which itself could be crap to start with.The whole debate is just pure hyperbole.Speakers sound different ENOUGH to start a useful debate as to whether the difference is 'better' to listen to,sadly,the same can't be said for any cable.

 

deleted because repeating what has been said above.

 

You see Ian, that's the bit I don't get. The test appears to be consistant with whatever point if view we held prior to it's taking place. As it is statistically insignificant, neither side of the arguement can claim any result to be at all meaningful. It's quite amusing to see objectivists claiming some kind of indication that their beliefs are bourne out by these flawed tests. I say 13 out of 15. You point me to the control test. You say 7 vs 6. I say system dependency and subjective preferences. Surely we both say it was pointless?

 

Not really. The results are essentially random, because the sample isn't large enough, and because the test didn't actually test whether the participants heard a difference, only if they were prepared to claim they heard a difference, which is a very different thing. The test also shows that two thirds of the participants were prepared to claim a difference even when the cables weren't swapped, which is an indication that they are unreliable. Given that the phenomenon of power cable audibility is an unproven hypothesis, for which there is absolutely no independent supporting evidence, this set of results, if it supports anything, tends to support the status quo.

The fact is, if these differences were clearly audible, there would be significant evidence for them by now. That evidence simply doesn't exist. The game's over. The differences must be either tiny or non-existent, the other possibility simply isn't credible.

-- Ian

 

Hi,

Note, power cables in a system of interconnected mains powered gear can be highly significant, hum loops are the low frequency illustration of that, RF is much more interresting in todays RF soaked world (I often wonder why we do not wake in the morning nuked to "well done", THEN AGAIN, maybe we do and just not notice).

Secondly, as the husband of a girl most people would consider to look so perfect they cannot believe it - well, if you live close enough with her you find she has a little cellulite, various birthmarks and other skin belmished and on occasion a rather disagreeable streak in her psychy. I still absolutely adore her, but I am also aware of the imperfections.....

As it happens, I'm an engineer, I have less tolerance for imperfect machines than for imperfect humans, machines are boring at best, unless they serve purpose, humans no matter how disagreeable are interresting.

Ciao T

 

Hi,

Information should not be censured, HOWEVER, behaviour which uses pseudoscientific means to claim as fact what cannot be supported by fact is not information. If such is repeatedly is claimed as "scientific proof" despite repeat critique and dipute it becomes deliberate disinformation.

I do not view the results with sadness as such, mostly because there where no results, except "no result". I view with sadness that much effort has been expended without the slightest chance of attaining any result or meaning.

Irelevant.

The system may have consisted of krell/wilson or stax or anything, or it may have been a morphy richards £ 20, that is irelevant.

Actually (ignoring the rest for brevity only) non of the above and omitted are true or relevant.

The fact is simple. The test was from the beginning weighted so heavily against any ability to draw any conclusions that any data generated is devoid of use, from the word get go.

That is without criticising the actual test setup (listeners, gear, etc) BTW.

Feel amused, but at your and not at my expense. Past that, try it one time. The results may surprise.

Or even better, do you feel up to an actual test of the blind methode, as opposed to applying it?

L8er T

 

Are you saying Chinese chess pieces super-glued to CD players has scientific basis?

 

Hi,

That depends on your definition of "scientific basis".

If you have a pcb which is supported on a few places or a thin piece of metal that is resonant, adhering a reasonable mass will change these resonances, as there are a lot of things in a CD Player that are somewhat suceptible to mechanical resonance (crystals, capacitors, mos/cmos IC's) there is certainly the possibility for all of this to add up to audible differences.

As I have nothing to proove to anyone this where I leave it, I make no particular claims (and I do not sell chinese chesspieces either) and merely suggest that you may wish to try it. I find it to be a useful methode. There is no particular need to use chinese chess pieces, but they are an inexpensive source.

Ciao T

 

Anything "can be" highly significant. The fact is, if, in general, power cables actually were highly significant, that significance would be clearly audible, and there would be unequivocal evidence for it. You can finesse round this basic fact all you like, the credibility gap is on your side of the debate until you provide some evidence.

RF is one of those things audiophiles love to worry about. On the surface, it seems it must be a very bad thing, and taking steps to reduce it must be a good thing. And, I suppose if you have an audible RF problem something ought to be done about it. But most audiophiles don't have an audible RF problem, they just like to worry that they might, and apply fixes to a problem they can't even hear.

-- Ian

 

Hi,

Well, first of all, the implication is of course that if something CAN be significant under certain circumstances we need to define next these.

I am not sure what credibility gap you are talking about.

It is trivial to illustrate that all mains powered audio gear is subject to various leakage currents into the chassis/signal ground. These currents must go somewhere if more than one piece of equipment is present and they are interconnected by conductive means.

Further, the current flowing in the mains cable is of a highly pulsed nature (not a 50Hz sinewave) with a lot of high order harmonics in most conventional gear, using torroidal transformers or switched mode supplies is especially notable.

If our mains cable has a high differential mode inductance or resistance we will experience a material voltage dropped which will invariably find it's way into the audio circuitry.

The final issue worth noting is the amount of RF in the air. On much commercial gear, when fitted with a standard £0.25 Mains cable I merely need to dial a number on my mobile to get a measurable (and audible ticking) output despite shorted inputs. Using for example shielded mains cables with some build in (ferrite) filtering which do not have to be expensive pretty much excludes the field from my mobile.

If you find all that incredible you may need to (re) take EE101.

BTW, NOTE that I am not in favour of "expensive" cables per se, however small scale hand build items do cost money.

In the case of mains cables I am VERY MUCH in favour of avoiding specialist cables as most of them do not have the neccesary safety approvals, which alone disqualifies from use. The key point from my end is that for any particular genre of cables there are reasons why there is a potential to cause audible differences, usually simply due to the designed in problems in much audio gear.

I have also observed some other items which seem to defy at this stage sensible explanation (the difference between silver and copper conductors, which becomes rather disturbingly large when transformers are wound with silver - not that I think the silver wound transformers neccesarily to be better BTW, another one is the effect quarz crystals in equipment - that is not the oscillators, but the ones you buy in the new age shop), but that does indicate to me a requirement to deny them.

So, bottomline, make sure you have actually attempted to understand what goes on, before making grand pronouncements and keep an open mind about the rest. Sadly the lack of actual serious investigation and understanding lineary leads to the extremes of charlatanery we can see in the fringes of audio accessories and which gives perfectly sensible people who actually do serious research and attempt to address real issues a bad name too, by being tared with the same big brush.

Ciao T

 

Quite so. My point being that, in reality, the significance of power cables seems to be purely theoretical, as audible differences between such cables appear to be tiny. There's certainly no evidence of the differences being any more than significant than this, despite the unproven claims of a few individuals who state the differences are obvious and large.

The gap between the reality of most people's experience (power cable differences not being audible, or not audible enough to be reliably identified) and the claims, despite all evidence, of a small number of audiophiles (power cable differences being significant and obvious). Anybody on the latter side of the debate has an awful lot of proving to do before they can expect to be taken seriously, and I'm getting bored with the inability of such people to provide even rudimentary evidence for their belief beyond saying, "I can hear the difference".

If I go into, say, Maplins, and spend, let's say, £1.50 on an IEC cable, would you expect this cable to have an abnormally high resistance? Or would you expect it to perform within the parameters required for the job of powering the average audio system?

You've said it yourself, mobile interference is trivial to solve, a couple of ferrite rings and an off the shelf shielded IEC cable from Maplins designed for computer use should be sufficient in most cases. Phono stages may need some additional isolation in the worst cases, otherwise audible RF should be a non-issue with the minimum of expense required.

On that we can agree.

Bottom line, make sure what you're describing is a real, repeatable phenomenon and not simply in your head, before theorising a new form of science to explain it. Occam's Razor applies to audio engineering too.

-- Ian

 

More amusement Thorsten.

The Author and TNT-Audio will NOT accept ANY liability for any form of Damage incurred to Live, Health or Property.

Sound familiar?

By all means set yourself up as a God like know it all if it suitably massages your ego, but at least make sure you do not contradict yourself.

 

Hi,

Note that what you are refering to was a DIY ARTICLE which stated very clearly the electrical safety implications and required the user/diy enthusiast to ensure they where in compliance with local laws, regulations or to accept the risk.

My comments here where strictly about the retail end of this whole thing. Even someone as ill intentioned as you seem to be should be able to get the difference.

You may also note that 3D Sonics does not offer any mains cable for sale (we do offer our customers Interconnects and Speaker Cables, as too many [other] commercial products are unsuited to the job).

L8er T

 

To me it is hypocritical to suggest an endeavor that involves risk while similarly stating the level of risk is personally unacceptable because of a lack of appropriate safety approvals.

You should recognise Thorsten that people will read your articles and because of your extensive technical knowledge, that I acknowledge, will tend to believe all is well despite the safety warnings. Irresponsible in my opinion.

Albeit a side issue to this thread.