Power cords

[thatguy]

If people can hear a difference why would you state that they are wrong, unless you think you know more than everyone else. Do you?

Let me fix that for you:

If people can hear a difference in a double blind test why would you state that they are wrong, unless you think you know more than everyone else. Do you?


When you are dealing with human subjects, you need to do better than sitting in your drawing room and writing a report after changing the cables. Of course, conducting real experiments is expensive and time consuming. But till then, all this talk is all in the realm of poetry, not science; which is fine as long as everyone, including you, understands what it is.

Disclaimer: I am a fence sitter on this topic. Power cord is the least of my problems right now. I do however hate it when people draw sweeping conclusions from crude limited experiments.

 

[digitalv]

Take a break and go listen to setup where a power cord can make a difference. Then post. Please.

Been there...done that around 3 years back in a studio environment...Could not make out any difference in a blind test. A colleague in the group claims to hear differences but could not correlate in multiple blind tests...

I don't claim to have golden ears but do I need to?... All you need is an unbiased mind...

My original query is still open...please post one scientific journal entry on this very topic...Or at the bare minimum support it with engineering logic....I'm waiting to learn...

 

[awedeophile]

As stated in a previous post on this thread, I have bought my power cables after trying them in my setup and being able to distinguish a particluar one in a blind A/B test.

OK.. you cant hear a difference... so does that mean we all shouldnt be able to?
I think just becuase you haven't experienced it, its unfair to say it does not exist.

With regards to measurements.... Resitors/Capacitors with the exact same measurements sound very different...

I dont have anything else to add here... so I'm off.. All the best..

 

[digitalv]

I think just becuase you haven't experienced it, its unfair to say it does not exist.

All I was asking is a logical or scientific reason why a power cord can make sonic difference...I have technical reasons (within my limits of being associated with the world's biggest HW R&D provider) to believe it wont. Am I not free to believe in science than black magic, heresy and placebo? I'm sure I am and like wise everyone is entitled to their beliefs and opinion.

Lemme reverse the the question you've asked me...Because you felt there is the difference from one power cord to another, does it make it right? It might have sounded right just for you.

If you've heard the difference, good for you...Enjoy and consider money and efforts well spent...If you are liking it, that's all it matters!!! To each his own...

 

[arj]

Thank god. :clapping: was giving up on this forum as all other audiophile forums have regular power chord fight and we were being soo tame.

Whew.

We are most likely going to either agree to disagree Or someone quitting the forum in a Huff.. The mystery/interest for me is figuring out which one of it we will end up with here !

 

[digitalv]

Thank god. :clapping: was giving up on this forum as all other audiophile forums have regular power chord fight and we were being soo tame.

Whew.

We are most likely going to either agree to disagree Or someone quitting the forum in a Huff.. The mystery/interest for me is figuring out which one of it we will end up with here !

I too have experienced the same fight on many international forums, but often the distinction was clear there with many snake oil companies or fan-boys or representatives fiercely fighting for what they think is right ...again without any technical backup... here I just don't know what the contention is. May be we like to justify our investment and to be frank we are in all our liberty to do so...No offense intended

Cheers!

 

[stevieboy]

All you need is an unbiased mind...

I'm waiting to learn...

Hi Digitalv,

Instead of coming from a theory of power cords are all the same, if you truly have an unbiased mind, you would take cognizance of the fact that quite a few people hear differences in power cords and then use your scientific tools and expertise to find out why this occurs. This is good scientific practice. You seem to have made up your mind and now want proof to the contrary, which is not indicative of true unbias or a spirit of learning.

I respect your position of power cords being the same, that's your own belief, but your methods to reach the truth seem to me to be far from taking every factor into consideration.

Also you seem to already believe only in measurements you are currently aware of and do not seem to want to ferret out what could be a new set of measurements that will explain why people hear differences. This would be to my mind a commonsense approach and one that strives to uncover some meaning for existing facts. If you discount the fact of people hearing differences it sure ain't a complete theory

I have changed power cords and interconnects on a complete stranger to audiophilia and that person has detected differences and asked what did you do, it now sounds like this, with a description. How would that be placebo when the person wasn't even aware of the importance of power cords in the audiophile world or even aware of the change I was making. It was an eyes closed test with no intimation of what I was going to do. I could very well have been demonstrating a new CD player for all the knowledge that person had of the test.

If you formulate a scientific test that incorporates experiences like the above it would be fair otherwise I'd say you're operating solely within what you (and current science) know, which I'm pretty sure ain't the whole story.

Regards

 

[digitalv]

Hi stevieboy

I agree to the methodology, but there should be an ounce of technical reason/logic to back it (at least vague technical reasons to begin with to justify the time and resource investment)...

Personally..I like to do such myth busting experiments and I'd try to be as unbiased as possible in the tests. Please trigger that just little logical/technical reasoning and I can take this further as soon as time and resources permits...

I hope you understand the limitation of a technical company not being able to have expertise on psychological effects like placebo and detailed analysis on those realms

 

[stevieboy]

Hi Digitalv,

The only logic I can proffer is that enough number of people hear differences in power cords. So now, what makes that happen? That would form the basis for a test. You could either find two things either all power cords test the same or test different. If they test the same, then there must be something you are not testing for which is causing the difference in sound.

Regards

 

[Hiten]

Bros, As said in previous post and you all agree that these are endless debates. And I agree with some of you that every thing can't be measured. So what can we do about it besides posting subjective view of believing it or not believing it ?
In my opinion both who believe and who do not believe should come together for audition and share their views. That's the only way. And to save this get together from possible hand to hand fight :lol: I said what is superior and inferior sound should be avoided. Only how much difference is perceivable and at what price. I have few more thoughts on this audition test which would respect both camp's opinion. So if that is happening it would be very much appreciated or else I am off to listen to some vinyls.

So much with the theories. Better to get together at some place and try it out.

you are my man bro.
Regards

 

[Hiten]

One more thing I would like to add is there should not be any love lost for each other. This is a lovely hobby and we should respect each other's difference of opinion.
Regards

 

[hifiashok]

my bet is on deepakgang, hiten and anyone else who is open, either ways.

i kno, double-blind, etc., kinds of tests with varying degrees of subjectivity and objectivity have been done numerous times in the past by people with differing measure of commitment to the truth and/or prejudices. people would have, in their understanding of the subject, made them as unbiased, reasonable and realistic as practically feasible, with the means/tools/software available at the time, looking at things +vely.

no telling, this particular interest group comprising of staunch believers, nay-sayers, intellectuals, learned members and professionals MAY actually nail it!?! finally!!! why feel been_there_done_that is an end all!?!

i find digitalv approaching things very reasonably. yes, from his past experience and scientific understanding he does not seem to have answers, if any are (or need to be) there. let us all give him his due as we expect to be given ours. so, he IS OPEN to give it another try. this is gr8. all those from the school who believe can do the needful, and also come to terms with the best methodology to use this time around, since there would be tons of documentation already available on all (almost) past.

all of us can only gain from an exercise like this one.

ground rules, of course, are imperative.

i found the pune hfv meet was very well planned and documented.

on another note, i guess all of us kno what 'some' dealers do when they want to sell us a particular brand/model/price point TV, right?

 

[odyssey]

Digitalv

Perhaps this is of some interest to you
http://www.hifivision.com/audio-video-accessories/1899-can-power-cables-make-difference.html

 

[digitalv]

Digitalv

Perhaps this is of some interest to you
http://www.hifivision.com/audio-video-accessories/1899-can-power-cables-make-difference.html

Could you please post the article number or the archive PDF containing the test...The posted link is taking me to the home page.

 

[hifiashok]

september 2008 issue?

 

[odyssey]

It is Sep 2008 indeed. here is the conclusion briefly (from another website)

-------

There is an article in the September 2008 issue of Affordable Audio where an electrical engineer uses an oscilloscope and spectral analyzer to measure noise in his power line with and without an upgraded power cord. The net effect is reduced noise in the power line due to the addition of the upgraded power cord. The reductions were in the 2 to 4 dB range, which should be audible. So, it seems the effect of upgraded power cords isn't to provide additional current to components, but to act as filters for noise that is contained within the power being delivered to a component

------------

 

[digitalv]

Interesting article and the experiment is worth repeating on my side. In fact we do a somewhat similar test on power supplies but just don't swap the cord...The objective is to see how much noise the power supply contributes to the DC output

I can however cite a few pin-holes to begin with after a quick run through the entire article.

1) The author seems to have used a single ended probe for measurement which by itself is notorious for noise pickup depending on its own proximity to noisy lines. No reference whether the cable positions remained the same through out the measurement. He should have used an active differential probe to begin with to see the real noise on the measured lines rather than coupled noises from the non shielded power cable and all sort of interference due to the long measurement probe itself.


2) There is no mention of an EMI/RFI filter at the input of the audio equipment power supply input. Such a filter is expected to do a lot better job than some fancy cable and a lot cheaper too (discussed before).

3) No note on the design of the audio equipment's power supply unit whether it is linear or switched mode nor how good it is in filtering ingress noise. From the results it appears quite poor in that department which is NOT usually the case.

4) No plot on the DC output of the internal power supply either...This would have revealed a clearer picture of the quality of the power supply unit.

5) The author is using a wall socket power directly (which obviously is a practical and more prevalent use case) whereas here we were discussing a balanced power input.

6) No impedance matching networks seems to be used to avoid reflections (not sure since no mention of it).

More after I analyse the FFT plots later...

 

[Thad E Ginathom]

We are most likely going to either agree to disagree Or someone quitting the forum in a Huff.. The mystery/interest for me is figuring out which one of it we will end up with here !

If you cannot tell that already, just by looking at the posts, then, obviously, your computer is unable to sufficiently resolve them





Oddly... My monitor has recently benefited greatly from a new power cord. It now no longer goes off when knocked, or makes those horrible electrical sparky noises indicating a plug grip that no longer grips.

 

[sidvee]

An interesting post on Shunyata's facilities and Caelin Gabriel's thoughts on power cords etc. Thought it would be appropriate to post here. BTW flamers,naysayers, skeptics,atheists- if you disagree - don't shoot the messenger :-( with berating posts. Please take it up with Michael Fremer or even better Caelin Gabriel himself .

The Audio Beat - DTCD Measures Up - Michael Fremer tours Shunyata Research and talks with Caelin Gabriel


Cheers,
Sid

 

[arj]

Thanks Sid..I remembered there was a paper but had missed this article

i remember a controvorsial post by Caelin many years back on the fact that since it is AC, the "last" 3 feet could be considered the "First" 3 feet as well...and thats what matters !
of course since i have some background in power distribution i dont take that literally but each component does add /subtract power characteristic which affecgs the local loop.