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Power Cables. Are they overhyped?

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It doesn't help that perception at all.

But as I said, this was 'somewhat' out of my hands. We have some fairly significant (and, sadly, probably well-justified) sensitivity toward this very subject elsewhere in the company, and a friendly email falling into the wrong inbox escalated quickly.

Fair enough.
 
Thank you all for your time and sensitivity on the matter. Once again, I regret having to be the instigator in this, and now regret having to get back in my box.
 
<kind of moderating>

I should point out that I really have no issue whatsoever with Alan, he's a good bloke who I've always got on with well and very much welcome posting here. I'd really hate for anyone to cancel a subscription or anything as a result of what is a publisher's misunderstanding. As such my moderation post shoud be read slightly tongue in cheek - I have been doing this a very long time now and have learnt very well how to deal with legal threats! ;-)

He's also a Half Man Half Biscuit fan, so he's OK with me.
 
Alan also wrote a nice review of Royd Sorcerers, wonderful little speakers I wish I had kept instead of selling to Vuk.

<Jedi Mind Trick>

Vuk, Sorcerers really are shit. Sell them back to me.

</Jedi Mind Trick>

Joe
 
I hate to break the news to you but a dielectric is not a shield. And you have beautifully illustrated why the statement about RFI was nonsense. Of course a better shield could help, but he wasn't talking about shields he was talking about dieletrics.

PS Having a PhD is more or less irrelevant to anything, except on creationist forums where it is always mentioned in relation to people holding absurd stupid views which would cause a 13 year old to fail his biology test.

re your first comment: fair enough...I stand corrected for my obvious and regrettable technical ignorance, I'm not an engineer nor a PhD engineer working in audio, so I not do I profess to have any technical background to debate any technical merits implied. I thank you for pointing out my technical ignorance and my misstatement based on his article.

Now on point:

(1) Is it a simple case to you that I simply misunderstood, confused and misstated DR Bews comments on RFI and dialetrics, but that his position overall is indeed valid ? If so please kindly confirm the same with a brief explanation just where, and in lockstep I do apologise in advance

Or.... is it a case that DR Bews comments overall are an indicated fantasy or the like to you?

Dr Bews published comments and his credentials and industry on-going audio experience as a designer and builder of high-end audio LFD electronics certainly appear persuasive and credible to me and likely to many more of us laymen and non-engineers.

If he in the first part and I as a layman in the second part are fully "out-to lunch" as you have directly implied, (and sure... I may well be after 35 years in this hobby that arguably brands me as an endangered failing Boomersaurus but not quite yet drooling on my pillow....) then before I lament that and resort to contemplating the lint in my navel,

please list all of
- your personal academic and professional qualifications,
- your system gear that is the lab test source of your opinions genesis,
- your personal audio industry verifiable experience, and
- your overall published or acknowledged professional track record

to support your stated position and opinions. It is a matter of credibility assessment now to assess this equally and fully and thus properly.
 
I do apologise to Alan and Tony, for in part, prompting the legal letter. I was hoping, that by spelling out the implications of their position, Keith and others would pause to think about the logic of their claims i.e. that an industry of manufactures and journalists are knowingly conspiring to promote claims they know are not true.
 
Dr Bews published comments and his credentials and industry on-going audio experience as a designer and builder of high-end audio LFD electronics certainly appear persuasive and credible to me and likely to many more of us laymen and non-engineers.

please list all of
- your personal academic and professional qualifications,
- your system gear that is the lab test source of your opinions genesis,
- your personal audio industry verifiable experience, and
- your overall published or acknowledged professional track record

to support your stated position and opinions. It is a matter of credibility assessment now to assess this equally and fully and thus properly.

Appeal to authority (logical fallacy)
 
re your first comment: fair enough...I stand corrected for my obvious and regrettable technical ignorance, I'm not an engineer nor a PhD engineer working in audio, so I not do I profess to have any technical background to debate any technical merits implied. I thank you for pointing out my technical ignorance and my misstatement based on his article.

Now on point:

(1) Is it a simple case to you that I simply misunderstood, confused and misstated DR Bews comments on RFI and dialetrics, but that his position overall is indeed valid ? If so please kindly confirm the same with a brief explanation just where, and in lockstep I do apologise in advance

Or.... is it a case that DR Bews comments overall are an indicated fantasy or the like to you?

Dr Bews published comments and his credentials and industry on-going audio experience as a designer and builder of high-end audio LFD electronics certainly appear persuasive and credible to me and likely to many more of us laymen and non-engineers.

If he in the first part and I as a layman in the second part are fully "out-to lunch" as you have directly implied, (and sure... I may well be after 35 years in this hobby that arguably brands me as an endangered failing Boomersaurus but not quite yet drooling on my pillow....) then before I lament that and resort to contemplating the lint in my navel,

please list all of
- your personal academic and professional qualifications,
- your system gear that is the lab test source of your opinions genesis,
- your personal audio industry verifiable experience, and
- your overall published or acknowledged professional track record

to support your stated position and opinions. It is a matter of credibility assessment now to assess this equally and fully and thus properly.

The problem is that you have portrayed this guy as someone who is credible when you have no basis to do so. You have taken his qualification as evidence what he says is correct without examining the facts and from a self admitted technically ignorant position.

So precisely how and why have you come to the conclusions you have?

His comments about dielectrics are just wrong. Anyone with a basic electrical/electronics understanding would furrow their brow and go WTF?
 
re your first comment: fair enough...I stand corrected for my [blah blah blah]
What he said, or is reported as having said, simply makes no sense. This is obvious to anyone, irrespective of high falutin' accomplishment who is has a cursory interest in electronics and a willingness to think.
I claim no great or even small credentials other than that I can think clearly and I tend to care about whether I understand things or not enough to check. If you do too you will be able to assess whether the point I have made is good.

I would however point out (if it helps) that Jim does qualify as something of an expert and he has confirmed the point.
 
r

Now on point:

(1) Is it a simple case to you that I simply misunderstood, confused and misstated DR Bews comments on RFI and dialetrics, but that his position overall is indeed valid ?


Dr Bews published comments and his credentials and industry on-going audio experience as a designer and builder of high-end audio LFD electronics certainly appear persuasive and credible to me and likely to many more of us laymen and non-engineers.



please list all of
- your personal academic and professional qualifications,
- your system gear that is the lab test source of your opinions genesis,
- your personal audio industry verifiable experience, and
- your overall published or acknowledged professional track record

to support your stated position and opinions. It is a matter of credibility assessment now to assess this equally and fully and thus properly.

His comments as reported here are incorrect or misleading. To whit: Simply putting dielectric like PVC, etc, around/between cable wires doesn't 'shield' them from RF. I can't tell if he is being misquoted at some stage or has misworded trying to over-simplify, or if this is for some other reason. I can only comment on what we've been presented with.

However One of the key points made already is that this isn't a matter of who has a PhD, Scout Badge, etc. Its a matter of the basic physics. Best to focus on what is said, not who says it.

If it helps you, though I can give some of my background.

Yes, I have a Piled higher and Deeper which I got in 1981
During my working life I worked for some years as an audio designer for the old 'Armstrong' company, and have continued to take an interest in the topic. I've also worked as a Lecturer - eventually as a 'Reader' - for decades at Uni and during that time supervised over a dozen research students to their PhDs, and taught heaven knows how many undergrads. I also wrote some books on instrumentation (undergrad honours level) and aspects of RF (research level). Plus articles for New Scientist, Nature, Focus, etc. Not confined to audio mags. I'm also an IEEE, AES, and IoP member still.

FWIW I 'won' two UK Prizes from the NPL for measurement systems I devised to make RF measurements to let them improve the *definitions* of the relevant standards. Had a long relationship working for them, along with my old research group.

However none of that changes the basic fact that you can look in the physics textbooks and see that EM radiation and fields will generally pass though dielectrics. You can also measure this if you like. Or simply note that capacitors generally have a dielectric inside them and pass AC. Indeed if you live in a home made of bricks (dielectric) with glass (dielectric) windows, you can probably note that your portable transistor radio may work without you needing to open a window.

So you can cheerfully disregard all the above personal history beyond noting it represents the sort of working background that prompted my comments on this matter. Nowdays, I'm just a retired old fart who writes a bit about audio because I find it interesting. I try to clarify technical issues in case it helps people to make their *own* judgements.

FWIW Curiously here, If anything, having a *bad* dielectic would be preferred if you want it to reduce RFI. Because lousy dielectrics like poor PVC tend to have a higher 'loss factor' (loss tangent is the term engineers may recognise here) than good quality HDPE or PTFE. But this isn't likely to be make much difference at the kind of RF frequencies that will affect most audio kit or propagate along mains wires.

I should also perhaps add that one of the measurement areas I got involved with with NPL many years ago was measuring the properties of dielectrics like PTFE, etc, from near dc up into the mid infra-red. This was of interest as my old group uses PTFE and HDPE for *lenses*. Glass is, of course, also a dielectric. But in the far infra red these polymers have lower loss.
 
Hi Julf - as mentioned in an earlier response I already make use of a very capable noise filter (MIT Z Powerbar), but wonder what extra noise that adds to the 'earth' line at the kit.

Also, would such a suppressor capacitor deal with noise on the ground line?



You may well be correct - what sort of impedance is such a cable likely to present to higher noise frequencies? Have you done any experimentation that might confirm this recommendation? I really am trying to understand if doing something more elaborate might provide a worthwhile return.

By the way, I think the normal ground wire in typical 2.5mm T&E cable used for a ring main is only 1.5mm (in fact even 4mm T&E that many would use for a dedicated HiFi radial supply incorporates only a 1.5mm ground wire also).

Cheers. Bill

insulated single core copper wire can be bought from any electrical factors, at a reasonable cost, check the regulations (with an electrician) and install to the requirment for your particular case. the earth point can similarly be installed, there is guidance on soil moisture content and resistance to earth. Should be good enough. PS protection from lightning strikes is a different case, probably that is where you have seen copper strip. Again practical specialists are capable of advising
 
Hi Westsea

The reason I mentioned copper strip and lightening strikes is the the short pulse associated with a lightening strike includes the high frequencies that I was concerned about. I doubt the normal 6 or 10mm earth cable is likely to have low impedance to high frequencies over a 25-35m run.

I've got trade accounts with a couple of electrical factors, so will be able to purchase fairly cheaply.

Cheers. Bill
 
The reason I mentioned copper strip and lightening strikes is the the short pulse associated with a lightening strike includes the high frequencies that I was concerned about.

No, the copper strip is to deal with the high currents involved with lightning.

I doubt the normal 6 or 10mm earth cable is likely to have low impedance to high frequencies over a 25-35m run.

Do you have any specific reason for your doubt?
 
I should state for the record that I'm a fan of Mr Sitcom's (sic) work. In fact I have a complete set of hifi Plush right back to issue one. While he's 'not the writer that Mr Gregory is', I greatly enjoy his audio ramblings and proclivity for HMHB and Ramstein.

He's an audio reviewer writing audio reviews and one of the better ones at that.
 
Given that the LFD manufactures amplifiers - NOT cables - what could the Founder / Chief Designer possibly have to gain by making this observation?

He immediately opens his company up to 43 pages (and counting) of abuse from self-proclaimed experts / skeptics.

His interpretation as to 'why' this an effect occurs - may be incorrect - but that is a different matter to whether it occurs.

@AKG - Obviously our Osiris amplifiers are lacking in some way ;-)
 
Given that the LFD manufactures amplifiers - NOT cables - what could the Founder / Chief Designer possibly have to gain by making this observation?

Feeding a belief system that keeps people buying "high end" audio products, perhaps?

His interpretation as to 'why' this an effect occurs - may be incorrect - but that is a different matter to whether it occurs.

Indeed. It also is no proof that it actually happens. So it might or might not happen, and his misguided explanation doesn't really make a difference this way or that.
 
Hi Westsea

The reason I mentioned copper strip and lightening strikes is the the short pulse associated with a lightening strike includes the high frequencies that I was concerned about. I doubt the normal 6 or 10mm earth cable is likely to have low impedance to high frequencies over a 25-35m run.

I've got trade accounts with a couple of electrical factors, so will be able to purchase fairly cheaply.

Cheers. Bill

I don't understand why the impedance to high freqencies is a matter of concern, like many here I am a retired engineer, and can understand the desire for, dare I say, 'overkill'. However my approach would be to start with the regulatory and safety requirements and add any resonable enhancement that would not change the intrinsic qualities of the system. Julf's view is same thing in more precise terms.

Trying to be helpful Cheers H
 
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