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Power Cables. Are they overhyped? Part III

Inescapable logical conclusions have been proven wrong on so many occasions in the world of science, you push, it moves forward is no longer an inescapable logical conclusion.

A bad scientist makes such a claim without testing being carried out, it's your personal view, as it is with a couple of others here, no one has tested out this theory.

Until they do, it's a cop out & a convenient get out clause, that's my personal opinion until proven wrong.

Its not an opinion its a fact. If the amp is noticeably affected negatively by the tiny possible difference that a mains cable could cause to the mains conditions then it is defficient in the area of psu, psrr and emc.

It is a design requirement to cope with varying mains conditions as this is guaranteed to be the case in every installation. There is guarenteed to be a varying level of voltage, waveform distortion and electromagnetic/ RF noise.

To convince yourself that it is anything else but a deficiency is delusional.

The test is that you (and others) adamantly claim that their amps are affected by mains cables. If this is the case, and you and others will argue till the cows come home that it is, thenyour amp cannot cope with very subtly varying mains conditions without noticeable variations in performance. This is not a virtue.

It is so simple that its utterly mind boggling that some choose to argue against the point.

If we take one aspect of mains quality, and I will lump it under the broad banner of RF:

EMC regulations

The Directive requires that products must not emit unwanted electromagnetic pollution (interference) and must be immune to a normal level of interference.

In essence the requirements of the Directive are very simple - it basically states that products must not emit unwanted electromagnetic pollution (interference) and, because there is a certain amount of electromagnetic pollution in the environment, that products must be immune to a reasonable amount of interference


Before you argue about the definition of reasonable you should consider the following. If you are one those having issues in this area (abnormal levels of mains problems) then your choices are, buy a better designed amp, fit appropriate filters, or use a regen. A mains cable on its own is never a credible or effective solution to any of the mentioned problems.
 
When I go to the opticians they put in two lenses. Which is clearer, 1 or 2?
By a sequence of these tests, I get to clearest vision.
I do the same with my hifi, listen to a and b and select the best.
Not everything is an improvement, or no change.
What is the difference between visual choice and aural choice?
I don't get this not believeing people about cables. If they hear a difference, they hear a difference, end of.
Clear sight is clear sight, clear audio is clear audio.

Im afraid its not that simple. Read Floyd Tools work on the bias issues with sighted speaker testing.

When you have your eyes tested you are effectively doing this blind. Excuse the pun. There is no influence in terms of frame aesthetics, price or brand. That comes after the lens definition.

Oh and add to that the lenses dont claim to to anything other than correct eye sight, which they unoquivically do........

Add to this the fact that you have no need to convince yourself the purchase was worthwhile and justified. You can see, without the glasses you cant. If you have just spent possibly hundreds on a mains cable you be inclined to convince yourself that, at best a barely perceptible difference, is actually there or significant.
 
Its not an opinion its a fact. If the amp is noticeably affected negatively by the tiny possible difference that a mains cable could cause to the mains conditions then it is defficient in the area of psu, psrr and emc.

Therefore the "design deficient" amp's sound is changed by the mains cable.

I think we are all pleased that you finally agree to this.

Mr ED
 
Hearing is simply another sense.
People can taste different things and express a preference.
Or can detect which is the smoothest object by touch.
Or select their favourite aftershave.
Never is there an uproar and demand to prove the sensory information.
Likewise with hearing, the difference for some is as palpable as any other sense, and why shouldn't it be?
People's sense of hearing is variable, and hence the disbelief.
Why would anyone lie about what they hear?
If I buy a £2000 lens for my camera and the pictures are no better than my £50 lens, would I pretend they were? Of course not, I'd return the lens for a refund.
So, the way i see it, there are two groups of people trying to convince the others of what their senses are detecting. Which is obviously pointless.
 
Hearing is simply another sense.
People can taste different things and express a preference.
Or can detect which is the smoothest object by touch.
Or select their favourite aftershave.
Never is there an uproar and demand to prove the sensory information.
Likewise with hearing, the difference for some is as palpable as any other sense, and why shouldn't it be?
People's sense of hearing is variable, and hence the disbelief.
Why would anyone lie about what they hear?
If I buy a £2000 lens for my camera and the pictures are no better than my £50 lens, would I pretend they were? Of course not, I'd return the lens for a refund.
So, the way i see it, there are two groups of people trying to convince the others of what their senses are detecting. Which is obviously pointless.

The analogy doesn't work for me. I'm all for people hearing what they want or buying what they want and all that good stuff. But it is simple enough to establish whether a difference is being heard or just claimed. No need for 'convincing' anyone.

If a difference is established, then which people prefer is of course a matter of opinion.
 
Yes I have and continue to do so, here is the 'how-to' link again.
https://www.puriteaudio.co.uk/single-post/2017/02/08/Level-matching-for-fun
IME perceived 'sighted' differences tend to disappear when conducted 'unsighted'.
Keith

The point I’m trying (and failing) to make is that the cable sceptics use lack of results from blind tests as evidence that the difference goes away under blind conditions. From this, they conclude that the difference is down to imagination/self-delusion. This is the stick with which subjectivists are repeatedly beaten. It is also an invalid conclusion to draw.

All you can conclude from a null test is that the difference claimed was not detected under the test conditions. Absence of evidence is not evidence of absence, and all that. If you wish to conclude that the result demonstrates that no actual difference exists, you have to show that the test is sufficiently sensitive, or else your conclusion is not supported by the test results.

Much mockery (notably and disappointingly from BE718) ensues when it is suggested that the test may induce stress or fatigue, which may blunt perception. No evidence to refute the suggestion is offered, it is just summarily dismissed. Yet there is a well-documented medical phenomenon known colloquially as ‘white coat syndrome’. I have seen its effects on me personally, where my resting blood pressure rises by 10-15 points when measured, my doctor now knows to ignore the first reading, let me relax a bit and take the second or third reading (which is always down by those 10-15 points). I have no doubt other, similar, ‘test stress’ phenomena are familiar to medical research the world over.

It is surely not in dispute that what is being tested in a blind test is the ability of individuals to perceive a small difference in sound. Thus it is the individuals who are the test subjects, not the devices used.

Similarly, it is surely not in dispute that fatigue and stress alter perception, and there appears to be evidence that fatigue can set in quite quickly if the same test piece is used repeatedly, or the same test is repeated frequently, especially among untrained listeners. The response to this is to say that you can use whatever test pieces you prefer, and take as long as you wish, which is fine but you still need to be able to show that the methodology has been sufficient to remove this fatigue (or perhaps ‘acclimatisation’ or ‘over-familiarisation’). From experience, my personal threshold seems to be around 4 or 5 repetitions of the same piece before confusion creeps in. Let’s not forget that, in order to be statistically valid, such tests need to undergo numerous repetitions. I would be very interested to know if the number of ‘correct guesses’ varies (declines) as the number of repetitions increases (I suspect it does), as this would establish some sort of baseline as to how many repetitions can be done before some form of fatigue, stress, whatever, starts to kick in.

As to the ‘how do you know it is subjectively audible if you can’t accept the test results’ argument (which is a fair point), start with two devices which are measurably different, and establish sighted subjective listening to see if there is a consensus among listeners that they sound different. Then move to the blind test, see if (how) the results vary. If they don’t, then you have a test which is valid for the degree of differences claimed for the sighted listening.
 
That's a good analogy for what I think is at the heart of all of these mains cable and similar threads — when some say they hear a difference they might be talking about their subjective perception, while others are talking about objective measurement.

The interesting thing is that even if I've confirmed to myself that A to B is the same distance as C to D, it doesn't alter my perception one iota. A to B still looks longer to me and that's all I have to go on when looking at the picture. I've been fooled, but so what?

Extrapolate that to hi-fi.

Joe

Let's not forget that the whole purpose of hifi is to fool the brain into thinking that musicians are performing in front of us. Given that our eyes tell us there are no musicians there, it is not a given that our eyes overrule our other senses every time. So why is it necessary that our eyes not be involved when testing kit? (Rhetorical question, by the way).

The thing is, hifi creates an illusion by messing with our heads. We are willing participants. If further messing improves the illusion, does it really matter whether the messing is scientifically proven, or not? This is a more philosophical argument, perhaps a moral and ethical one when cost enters the equation, but personally I think it is one worth pursuing.
 
Its not an opinion its a fact. If the amp is noticeably affected negatively by the tiny possible difference that a mains cable could cause to the mains conditions then it is defficient in the area of psu, psrr and emc.

It is a design requirement to cope with varying mains conditions as this is guaranteed to be the case in every installation. There is guarenteed to be a varying level of voltage, waveform distortion and electromagnetic/ RF noise.

To convince yourself that it is anything else but a deficiency is delusional.

The test is that you (and others) adamantly claim that their amps are affected by mains cables. If this is the case, and you and others will argue till the cows come home that it is, thenyour amp cannot cope with very subtly varying mains conditions without noticeable variations in performance. This is not a virtue.

It is so simple that its utterly mind boggling that some choose to argue against the point.

If we take one aspect of mains quality, and I will lump it under the broad banner of RF:

EMC regulations

The Directive requires that products must not emit unwanted electromagnetic pollution (interference) and must be immune to a normal level of interference.

In essence the requirements of the Directive are very simple - it basically states that products must not emit unwanted electromagnetic pollution (interference) and, because there is a certain amount of electromagnetic pollution in the environment, that products must be immune to a reasonable amount of interference


Before you argue about the definition of reasonable you should consider the following. If you are one those having issues in this area (abnormal levels of mains problems) then your choices are, buy a better designed amp, fit appropriate filters, or use a regen. A mains cable on its own is never a credible or effective solution to any of the mentioned problems.
I will pass this info on to a few people, see what they think on the subject as there are only a couple here stating this, which in itself is quite a low average.

You are basically stating, every single Naim amplifier is deficient, Naim amps react quite sensitively to cabling of any kind, mains included, this is where your logic falls flat for me.

My mains are fine, I never experience mains issues, pops, clicks, etc..
I still don't see a difference with buying a regenerator, an amp should be able to cope with mains fluctuations too, a regenerator only addresses these issues, they cost hundreds too.
 
BE also 'knows' that hifi supports can't and don't make a difference.

Once, a few years ago, I went to help a friend sort his hifi out. After some listening, he went to make a cuppa and, while he was out, I made an invisible change to the system. When he came back in, we played another track and he almost immediately looked at me and asked 'what have you done, that's miles better?'.

I'd inserted some small, inexpensive Quadraspire acrylic feet between his amp and the glass shelf it rested on, they were barely any higher than the amp's own feet, and effectively invisible from the listening position. The difference was obvious.
 
The point I’m trying (and failing) to make is that the cable sceptics use lack of results from blind tests as evidence that the difference goes away under blind conditions. From this, they conclude that the difference is down to imagination/self-delusion. This is the stick with which subjectivists are repeatedly beaten. It is also an invalid conclusion to draw.
You could of course draw this 'invalid' conclusion. You could also draw the conclusion that thus far nobody had demonstrated an ability to discriminate between mains cables in ABX DBTs. And you might also reasonably say that the onus is on those who believe mains cables make an audible difference to do so.

Much mockery (notably and disappointingly from BE718) ensues when it is suggested that the test may induce stress or fatigue, which may blunt perception. No evidence to refute the suggestion is offered, it is just summarily dismissed.
In response to a previous post of yours arguing the same, I proposed a simple way to check whether this is a real effect: simply run a couple of Stroop tests before and after the DBTs (see my post #657 in Part II.)
 
The thing is, hifi creates an illusion by messing with our heads. We are willing participants. If further messing improves the illusion, does it really matter whether the messing is scientifically proven, or not? This is a more philosophical argument, perhaps a moral and ethical one when cost enters the equation, but personally I think it is one worth pursuing.

Absolutely worth pursuing. Placebos work. But it is pretty important to know if medicine X has an effect beyond the placebo effect - if the effect is only due to the placebo effect, you could use a medicine that is cheaper and has less harmful side effects. Likewise, if you find that the benefit of an "designer" power cable is purely due to expectation bias creating an improved illusion, you could accomplish the same illusion cheaper...
 
NO

To claim any piece of hifi equipment has been improved because an improved mains lead improves the sound needs to be proven to be so.

Ball - Court - Yours.

Good luck, you will need it, faries and electrons are not a good engineering mix.
It needs to be proven by those claiming this, I am not.
 
Even if mains cables did effect SQ ,due to placebo or poor amplifier design that effect is tiny compared to the real and measurable benefits of understanding your room and the integration of your room and loudspeakers.
I find it surprising that serious listeners will spend a considerable amount on accessories yet will not consider tackling fundamental acoustic issues .
Keith
 
The test is that you (and others) adamantly claim that their amps are affected by mains cables. If this is the case, and you and others will argue till the cows come home that it is, thenyour amp cannot cope with very subtly varying mains conditions without noticeable variations in performance. This is not a virtue.

Mains regeneration....why...what's the difference here, if an non deficient amp copes with such fluctuations why pay hundreds for one, maybe because they are an accepted way of removing fluctuations, which is fine, they should not need removing according to your logic, the mains fluctuations should have zero effect on a well designed amp according to you.
 
Hearing is simply another sense.
True and generally speaking amenable to similar testing methodologies (give or take). Blind testing is the commonly applied methodology in perceptual science generally. I and others have been urging throughout this thread to step back and apply what is known in other areas (both on the engineering side and the perceptual side).

But speculating on one area based on speculation about another?
People can taste different things and express a preference.
Or can detect which is the smoothest object by touch.
Or select their favourite aftershave.
Never is there an uproar and demand to prove the sensory information.
See above. There are countless examples of people making incorrect assumptions based on sensory information. There are examples involving all the senses.
And uproar sometimes. But there is only uproar if people don't like the result.
Likewise with hearing, the difference for some is as palpable as any other sense, and why shouldn't it be?
[palpable indeed. See multi-sensory integration]
People's sense of hearing is variable, and hence the disbelief.
Why would anyone lie about what they hear?
.
who says anyone is lying?
In tests there is a systematic bias towards "sounds different" even when presented with two identical things. This is covered in one of Tom Noussaine's AES papers.

People don't lie, they are just wrong. And having some people think that two things are different when they are the same is not surprising; it is predictable.

Really- if you are interested in this stuff, it's fascinating.
 
Therefore the "design deficient" amp's sound is changed by the mains cable.

I think we are all pleased that you finally agree to this.

Mr ED

Errol why do you persist with this, its context been explained a dozen times. You are either very dim witted or trolling.
 
People don't lie, they are just wrong. And having some people think that two things are different when they are the same is not surprising; it is predictable.

Can this happen in a blind test where identical amps, speakers, cd players, cables etc are concerned, in your opinion.
 
Hearing is simply another sense.
People can taste different things and express a preference.
Or can detect which is the smoothest object by touch.
Or select their favourite aftershave.
Never is there an uproar and demand to prove the sensory information.
Likewise with hearing, the difference for some is as palpable as any other sense, and why shouldn't it be?
People's sense of hearing is variable, and hence the disbelief.
Why would anyone lie about what they hear?
If I buy a £2000 lens for my camera and the pictures are no better than my £50 lens, would I pretend they were? Of course not, I'd return the lens for a refund.
So, the way i see it, there are two groups of people trying to convince the others of what their senses are detecting. Which is obviously pointless.

Its not a case of lying, its bias created by well known and understood psychological responses.
 
One for BE, forgot to ask this earlier, what is it's roll of the mains cable in rendering the amp deficient.

If the cable changes the sound, which has been tested blind in my circumstances, taking lying out of the equation as mentioned a few times recently, what is the cable doing here.

I have sent a message to a well regarded company for their views on this, I have included your earlier post for them to munch on, hopefully I will hear back in a few days or sooner.
 
Much mockery (notably and disappointingly from BE718) ensues when it is suggested that the test may induce stress or fatigue, which may blunt perception. No evidence to refute the suggestion is offered, it is just summarily dismissed. .

The mockery is due to the blanket excuse of "stress or fatigue" to discredit any kind of test. That's why its summarily dismissed.

While there may be a percentage of people that react this way, its simply not credible that its enough of a problem to invalidate any kind of testing. Its also not credible to insist it would mask any significant difference for a wide range of individuals. If you really do need to be in a Zen like state and had months of exposure to the system prior to being able to discern a difference, then its difficult to take said difference seriously as being of any significance whatsoever.
Even if it is personally significant to an extremist audiophile.
 


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