Our very own Ethan posted a limk to real science in a thread in the tweak section and was soundly bounced. They even went so far as to delete all his comments. They wnt zero part of real life over there it seems. I have to use a IP hide to post because they bounced me for even having the thought of asking them to consider science.

Its a shame but hey more money for the snake oilers.

That is certainly nutz ! Ethan is an unequivocated authority in this field.

Tim

Morons.

preaching pseudo science is no no

Our very own Ethan posted a limk to real science in a thread in the tweak section and was soundly bounced. They even went so far as to delete all his comments. They wnt zero part of real life over there it seems. I have to use a IP hide to post because they bounced me for even having the thought of asking them to consider science.

Its a shame but hey more money for the snake oilers.

Perhaps you should revisit the site..

If you look now, you will find that he was not deleted, he was "moved to a more appropriate venue". If you click the link that is provided, you will find that you are re-directed to prophead, which is supposed to be the venue for technical discussions. I was among the posters bounced, and unfortunately, my jpegs didn't go along for the ride, but were lost.

Ethan is still welcome there, and I wait to see if he is really willing to discuss anything technical there. (visits to prop typically invoke a gag reflex, I wouldn't be suprised if Ethan decided not to discuss there). But since the site update, they allow html as well as hosting multiple jpegs, embedded anywhere within the text you desire...absolutely great for detailing technical explanations..

Did you ever look up IEEE 1050? Section 4 basically details what I'd been trying to teach you, although they use neat words like "aggressor circuit" and "victim circuit". I detailed it a bit on the thread you ran away from..Ethan would also do well to visit the IEEE guide 1050 and my writeup, as it does indeed contradict his own site w/r to powercords.

Cheers, John

Perhaps you should revisit the site..

If you look now, you will find that he was not deleted, he was "moved to a more appropriate venue". If you click the link that is provided, you will find that you are re-directed to prophead, which is supposed to be the venue for technical discussions.

Oh I see so providing any sort of real answer to a real question in the forum it was asked is not kosher either. Etahn provided a real answer for this and they decide he has too much science behind him so lets move him.It is a free forum but they just swim in snake oil.

And yes I did read the section you posted. And while like I said what you did worked. Your the only one doing it. And I still stand by what I said when I called the other audio guy where you work with an idiot for not knowing how to solve a basic issue. And again you are the only one I have ever run into who fixed his ground loop your way. And again I will say when you are ready to step up to the AES plate and tell us all we have been doing it wrong then we can talk.

links?

Oh I see so providing any sort of real answer to a real question in the forum it was asked is not kosher either. Etahn provided a real answer for this and they decide he has too much science behind him so lets move him.It is a free forum but they just swim in snake oil.

Actually, he just posted a link to his own page. But they are rather inclined, at tweak and cables, to disdain any kind of technical discussion. Historically, the forum tends to protect the non tech people from technical discussion, which I actually do not agree with in principal. But I certainly understand the reasoning, as the arguments go without end..

As for Ethan's "300 feet to the pole schtick"...where to start...boy, is he ever incorrect..Reminds me of the opening scene of MASH, where they are looking for the helicopter, and it comes in behind them...oops.

A lot of what he says is dead on. But not all..


And yes I did read the section you posted. And while like I said what you did worked. Your the only one doing it.

Actually, if you did read IEEE 1050, you would see that I am NOT the only one doing it. Turns out, what I understand has already been considered by a professional organization, as well as partial incorporation into NEC. (note, I am not the origional source for the information within 1050. I developed the knowledge back in 1978, prior to the IEEE 1050 current issue, basically because I had to.)

And I still stand by what I said when I called the other audio guy where you work with an idiot for not knowing how to solve a basic issue.


The first words out of your mouth were that he was an idiot. If you recall, he uses the exact same kind of equipment YOU use to solve the issue. So, please explain to me why YOU do not fall under the descriptor "idiot", when the one you called that does EXACTLY what you do??HMMM?

And again you are the only one I have ever run into who fixed his ground loop your way.

So what? All that means is you don't get around, but rely on the equipment built by others to solve problems you cannot. The equipment that others designed and built to solve your problems is entirely inadequate for many industrial problems. For those real problems, understanding is needed. I presented the understanding so that people like you could avail yourself of the technique should you ever need to. Knowledge is a tool, the more tools....the better.

And again I will say when you are ready to step up to the AES plate and tell us all we have been doing it wrong then we can talk.

Step up to the AES plate and do what? Teach them how to read IEEE papers? Re-teach them Maxwell's equations and the ramifications?

The fact that the AES is unable to integrate the knowledge of another organization is not my problem. To be honest, I'm sure that some of the AES guys actually can read and understand IEEE or APS or Physica papers, but I haven't met them yet. So far, my experience with AES type guys has been rather mixed, some are rather knowledgeable in a small subset of the whole, while others can't figure out how to engineer their way out of a paper bag..with a clearly marked exit.

Then some come in, both barrels blazin, talking glibly about something they do not well understand.. Like the way you came in..

Cheers, John

links?
I'll try..
Here's the link to the prophead thread where Ethan's post and all below were sent.
http://www.audioasylum.com/cgi/vt.mpl?f=prophead&m=33470

Here's the link to the IEEE 1050 paper that was put up by FreeFire (thank you again..)
http://ieeexplore.ieee.org/iel5/10160/32470/01515972.pdf?arnumber=1515972

Here's the link to where I discuss section 4 of the IEEE paper, as well as a discussion on the error within the 1050 paper regarding shields and shield currents. The description they give is actually applicable only to superconductors.
http://www.avsforum.com/avs-vb/showthread.php?p=10519254&&#post10519254


Hope these work..

Cheers, John

The first words out of your mouth were that he was an idiot. If you recall, he uses the exact same kind of equipment YOU use to solve the issue. So, please explain to me why YOU do not fall under the descriptor "idiot", when the one you called that does EXACTLY what you do??HMMM?



So what? All that means is you don't get around, but rely on the equipment built by others to solve problems you cannot. The equipment that others designed and built to solve your problems is entirely inadequate for many industrial problems. For those real problems, understanding is needed. I presented the understanding so that people like you could avail yourself of the technique should you ever need to. Knowledge is a tool, the more tools....the better.




I called him an idiot because he thought he could solve his issues to with RF mics. He didn't understand you still had to patch the receiver into the system.

As far as using the same gear I do and relying on others tools. Well it is not practical to wind hundreds of feet of cable around each other be it on a tour or in my current Vegas show setting. So we use the tools designed by folks who know how to fix problems along with using the correct gear and cable for the job.

What possible audio industrial applications exist that I couldn't solve with the correct gear and tools? I have been in plenty of badly wired buildings and never had to rely on boy scouting my systems to make them work.

And you may very well have presented tools, your way of doing it turned more than just me off if you read your thread, and you just dismiss tools and those who have presented reliable papers and ways of doing things. I don't see your name on any of the papers or other reference guides used by our industry.

As far as the AES goes if you have a great idea stop presenting it here and step up to some real peer review.

Now please don't pollute this thread as well.

The description they give is actually applicable only to superconductors.




Great I love apple to orange guys. This does not even apply to this thread or the other.

The mods need to just lock this thread down. You are on my ignore list as well now.

Can you summarize your differences with Ethan regarding the power cord thing, John?

I called him an idiot because he thought he could solve his issues to with RF mics. He didn't understand you still had to patch the receiver into the system.


No, he used them in addition to some rf isolators of some sort, line in to the transmitter, line out at the receiver. The beauty of this appears to be that the receiver is at the system board, so there's no building ground issues. And he used DI's, as well as some line xfmrs..

As far as using the same gear I do and relying on others tools. Well it is not practical to wind hundreds of feet of cable around each other be it on a tour or in my current Vegas show setting. So we use the tools designed by folks who know how to fix problems along with using the correct gear and cable for the job.

You are an idiot (your word). Either that, or you do not understand english.

My friend uses the same tools you do, to get the job done.

I, on the other hand, used my own equipment in the same venue as he does, but fixed the issue I had very cheaply in less than ten minutes, by guile. (I'm from lonGUILEland) (sorry, had ta do that)...

I did not fix his setup, I used my own. His is without hum, but he needed all that ancillary stuff that you use. I did not.

As for practicality, I stated up front that what I did was only practical for a small setup such as mine, where the source board uses little power and can be used with one extension cord.

You really need to read more slowly. I never recommended twisting a thousand cords together to woik Las Vegas (oooh, las vegas...what happens there stays there).

What possible audio industrial applications exist that I couldn't solve with the correct gear and tools? I have been in plenty of badly wired buildings and never had to rely on boy scouting my systems to make them work.

Run a mike pair over a half megawatt 12 phase power supply alongside a half kilowatt 20 Khz PWM motor drive bundle that oscillates at a meg, then tell me how you'd solve it.. (that was last weeks problem for me).

And you may very well have presented tools, your way of doing it turned more than just me off if you read your thread, and you just dismiss tools and those who have presented reliable papers and ways of doing things.

No, don't be stupid. You claimed that papers you linked reinforced your erroneous position (which they did not), and incorrectly state that I discounted the entire paper. Diversionary tactics, dude..

I don't see your name on any of the papers or other reference guides used by our industry.

And you probably never will. Why would I bother? Your industry has a long way to go, and I really have no interest in babysitting.

You will find some of my contributions in the textbooks that are used to teach engineers like you, but again, I have no interest in whether or not you realize where it came from.

As far as the AES goes if you have a great idea stop presenting it here and step up to some real peer review.

Quite honestly, at my level of peer review, you can't understand the concepts. Why would you suppose that "AES" is at my level?

Now please don't pollute this thread as well.

This thread was started by you, you ranted incessantly without knowledge (gilbly is the term). In this particular case, you blasted the other forum for deleting Ethan's post. But yet, there is it, at props for all the world to see..

Did I see you say.....Oops, my bad???

Nope.

Cheers, John

Great I love apple to orange guys. This does not even apply to this thread or the other..

There was a point to that rant??? Man, you have a real problem..

I pointed out specifically where IEEE 1050 "steps up to the plate" and describes exactly what I have been showing all along...as an added extra bonus, I pointed out one section of the paper which is incorrect. Something that people at your level will never figure out, but I just happen to use every so often. And, I might add, plays a role in the ground loop sensitivity of a shielded line level run.

The mods need to just lock this thread down. You are on my ignore list as well now.

Cool, now you emulate an ostridge. When you want to learn, you know where I'll be. But don't rely on the moderators to quash a discussion you are unable to follow, that's the cheap way out.

BTW...before you stomp off whining like a baby, remember this:

For any professional audio needs I may have in the future, I have absolutely no problem with asking your advice. I've watched your posts, and am quite impressed with what you know and understand regarding professional audio. Nuff said..

Cheers, John

Can you summarize your differences with Ethan regarding the power cord thing, John?

Sure.

His linked "paper" disses power cord issues using the "miles and miles of wire" argument.

His argument is correct if one considers ONLY the voltage waveform which enters the equipment. Presumably, the designer can make the power supply sufficiently good that it rejects, filters, or otherwise ignores the crap that actually exists on the AC lines.

His argument is incorrect in that it does not consider the issue of the safety ground. Because of safety concerns, we all have to use some kind of grounding scheme. The loop that is formed by the safety grounds and the interconnecting cables, is within a rather messy e/m environment. This forms the classic ground loop which is to blame for so much hum.

The nature of these loops, is that they generate a voltage when the magnetic field goes through the loop. That voltage is proportional to the strength of the field as well as how fast the field changes. IOW, when the frequency of the magnetic field triples, the voltage also triples. (triple is the first harmonic of a haversine...180 hz..)

So If you have audible ground hum and somehow reduce it by manipulation of cable position, you may get it below some threshold, but then...are you done???

NO. Current noise on the line is not all 60 hz, nor 180, nor 300....the poweramp can cause audio frequency currents also, depending on the supply design. It also can shunt line noise via filtering, broadcasting this as well to the ground loop.

I corrected the 1050 blurb about shielding because the assumption that the shield is sufficient is correct only for superconductors, all others have resistance. The ground loop resistance, which defines the shield "anti-current", prevents full negation of the hotwire induced voltage, meaning that the shield connections, the shield resistance, the chassis to IEC resistance, the outlet GROUND contact resistance, all play in setting the shield bucking current and field.

Ground loop induced hum is real, and it is the lower frequency part of the loop's pickup. Ethan ignored it because he is "old school" and thinks it's only 60 hz. It is not.

Cheers, John

I'm not so sure that's where Ethan was going John. I've got the feeling is that he is of the general position that swapping out competent power cords for audiophile versions - the 5n silvers, etc. - is quite unlikely to result in the sort of claims (pick your favorite(s)) made by practitioners.

I'm not so sure that's where Ethan was going John. I've got the feeling is that he is of the general position that swapping out competent power cords for audiophile versions - the 5n silvers, etc. - is quite unlikely to result in the sort of claims (pick your favorite(s)) made by practitioners.


I have confidence that you may be correct with respect to his position. I also take issue with all that 5n stuff, as well as some other silly things such as cryo changing the metal..(I work with cryo a lot, and nobody here ever sees any difference ever w/r to how the wires perform. In fact, blindly cryoing anything scares me w/r to reliability...I've seen nobody actually design commercial audio (professional either) to withstand cryogenic cycling.. I'm suprised that so much actually survives the cycle, nevermine work at all. (note: you would be suprised how many superconducting magnet vendors actually do not design for cryogenic operation very well either..)

However, Ethan did not specify what he was speaking of, but left it as a blanket "miles and miles" thing. Which I pointed out, is incorrect.

I had hoped he would discuss this online, but given the signal to noise ratio at prop, I fear he will choose the "smart" path, which is to avoid prop. I cannot blame him if he chooses that.

Cheers, John

Well, that's my take on how Ethan views the whole power cord thing. I'm not so sure everything that's said to be cryo treated is, in fact, cryo'd. There's a fellow who supposedly cryo's stuff that people send him. He says he sends it to NASA. Now I once sent an inquiry there, mentioning the person's name who supposedly does this work, and got a reply that said basically, 'HUH'? So, who really knows if it is done by those who say they do it. I can see it having an effect on things like tubes but that's just because you'd cause things to bend at different rates and that'd change the position of things like the anode/cathode with respect to each other.
But anyways, it seems that you probably were heading down a different road than Ethan was with his miles of cable thing hence what appears to be confusion and all that other good stuff.

Our very own Ethan posted a link to real science in a thread in the tweak section and was soundly bounced.

LOL, I haven't gotten there yet today. I feel like the guy in that joke who reads the obits every day to see if he's still alive. I guess I'm not! :D

One thing that shocked me in that thread was when someone pointed out that discussing Double Blind Testing is not allowed. Say what?! But it gets worse. As the thread at the appropriately-named Tweaker's Asylum has evolved over the past few days, I've been involved in another science-versus-belief thread at Steve Hoffman's forum. Guess what? At that forum you're not allowed to discuss objective versus subjective observation.

It kills me that the believers are so insecure in their position, and they know they don't have a leg to stand on logically or technically, that all they can do is ban certain topics and/or certain people.

I was also banned at Audioholics for the same thing. AH is usually well based in science, but Gene and Clint who run things there have their own belief system that sometimes gets in the way of common sense. In that case I was banned for daring to question the claims of Audyssey for their room "correction" system. I know I can be a bit of an overbearing know-it-all some times. :D But in this case I was polite and stuck to the facts. After about five pages they knew they couldn't refute any of my points, so they just banned me.

Cowards! :D

--Ethan

John,

I have confidence that you may be correct with respect to his position.
Right, as Chu said my real objection is to people being conned into believing they should spend more than $2.00 for a power cord. In the larger picture it comes down to companies like Shunyata making claims they can't possibly back up, and not being able to show proof that the audio quality is improved or even changed. So instead they invent "new science" and, like vitamin and supplement vendors, try to convince people that audio engineers don't understand how and why the products work.

Related, a few months ago I put this Fraud Report (http://www.ethanwiner.com/fraud.html) on my personal web site to expose unethical companies in the acoustic treatment industry. One of those companies, Cathedral Sound, took exception to my portraying them as either dishonest or incompetent. (Take your pick...) At the time I honestly didn't know if they believed their own snake oil or if they knew their products can't possibly work. Well, I recently found out that it's incompetence. :eek:

They just sent me four of their magic panels to test in the RealTraps lab, and it's obvious from our email exchanges they actually think the results will be favorable. Hoo boy. My partner and I will run some ETF tests this weekend, and I'll update my Fraud page with the results. I did warn them though! :D

--Ethan

Well, if you want to get banned over at Hoffman's site, just casually mention something about stealing masters from the studio...:D

You mean that company doesn't even test their own products? Why, I never!

Quite honestly, at my level of peer review, you can't understand the concepts. Why would you suppose that "AES" is at my level?


Cheers, John
I don't understand. You don't want to present to the AES because they are not at your level, but you come to AVS to post and expect understanding.

It kills me that the believers are so insecure in their position, and they know they don't have a leg to stand on logically or technically, that all they can do is ban certain topics and/or certain people.


That's one point...don't forget that the owners also want it to be a secluded enclave for their point of view.. Hey, it's the rules..I do not necessarily agree with them, but abide by the rules..



I was also banned at Audioholics for the same thing. AH is usually well based in science, but Gene and Clint who run things there have their own belief system that sometimes gets in the way of common sense.

He he..I was almost banned there for presenting evidence that biwiring is different from monowiring...go figure.. :p

Cheers, John

John,

Right, as Chu said my real objection is to people being conned into believing they should spend more than $2.00 for a power cord. In the larger picture it comes down to companies like Shunyata making claims they can't possibly back up, and not being able to show proof that the audio quality is improved or even changed. So instead they invent "new science" and, like vitamin and supplement vendors, try to convince people that audio engineers don't understand how and why the products work.
--Ethan

I also blast the idiotic explanations should I see them. And yes, there are so many.

Nonetheless, your linked page is in error with respect to the blanket assertion of powercords cannot make a difference (biwiring also, but that's a different day :p ..).

It's time to revisit, eh? I'm game..

Cheers, John

It's time to revisit, eh? I'm game..

Cheers, JohnCompetitive "Maybe" ??? for sure

I don't understand. You don't want to present to the AES because they are not at your level, but you come to AVS to post and expect understanding.

What I do, and what I work on, is a kinda esoteric, with very niche thingamabobs.
Very few in the AES will understand what I'm talking about w/r to what I care to present on.

My solution to the audio/linecord/noise/loop thingy, which worked perfectly first time every time, I believe is worth explaining to posters here, because ground loops are so common and sometimes so difficult to fix. Why would I want to present this to the AES? It's been documented elsewhere, in this case, the IEEE.

My assertion that star grounding has inherent flaws is of the same generic problem, and I'm confident someone somewhere has already published most of what I'd recommend to get around those flaws. My guess would be RF pubs. But my work does not require I publish simple stuff like this. I have to publish the complex stuff I work on.

What I enjoy in forums is speaking to real people, and discussing real problems. Sometimes, I can help, and sometimes I receive help... Many times, I have to consider a problem from a different point of view from that of my own, and that is the most exciting part.

My understanding of biwiring is a direct result of that, which would never have been the case had I never discussed anything on forum. Do you believe a presentation to AES would be received on biwiring?

Pigs will fly first..

btw, I do not use biwiring. I do not consider it practical for my needs.

Cheers, John

My solution to the audio/linecord/noise/loop thingy, which worked perfectly first time every time, I believe is worth explaining to posters here, because ground loops are so common and sometimes so difficult to fix.
Cheers, JohnCould you go over it again. I can't find the thread, but I would like to try it as I can induce a ground hum and I want to see if it works as stated.

http://www.avsforum.com/avs-vb/showthread.php?t=832061

http://www.avsforum.com/avs-vb/showthread.php?t=832061Thankk you. I recently encountered a hum but fixed it (a different method), but I wanted to try this.

Oooh, private arguments. I love them.

Competitive "Maybe" ??? for sure

No. It is an invitation to revisit a concept, and discuss it online. Nothing more, nothing less.


Oooh, private arguments. I love them.
Just go away.. ;)

Actually, a lot of times these kind of "arguments" really spur a lot of thinking. It is best when the players do not get emotionally involved to the point where they begin to post derogatory comments to others, like calling people idiots, or not actually reading and understanding what has been said. Speco indeed jumped the gun and started in without understanding what was said, nor the underlying e/m theory used in the solution. To me, that makes him both impatient and knowledgeable (yes, that was the correct word). Certainly not bad traits in themselves, but sometimes together they can trip one up.

The ability to acknowledge one's error, regardless of the type, is also nice, but I see far too little of that on any forum I travel.

Cheers, John

Thankk you. I recently encountered a hum but fixed it (a different method), but I wanted to try this.

Good luck, keep us posted. Details and pics would be nice.

Cheers, John

John, how would you attack the following type of scenario? A person has an existing system - receiver, player, speakers, sub, cable box, tv - and has no problems whatsoever. He decides to he'd like to add an amp. Once he does, he finds he now has a hum. Let's look at two scenarios.

1) The amp has a three pronged cord.
2) The amp only has a two pronged cord.

John, how would you attack the following type of scenario? A person has an existing system - receiver, player, speakers, sub, cable box, tv - and has no problems whatsoever. He decides to he'd like to add an amp. Once he does, he finds he now has a hum. Let's look at two scenarios.

1) The amp has a three pronged cord.
2) The amp only has a two pronged cord.

My first q"s...what's humming, sub or speakers. Is the amp being used for the speakers now instead of the receiver? Or, more speakers. Setup needs to be clearer as well as where the hum is emanating..

The description is insufficient to allow total debug, since so many things are in place. The basic first step is to look for anything that alters the hum level. I'd look at manipulation of all the cords and amp placement as the first troubleshooting steps. Unplug each item independently, see if a sensitivity exists. There may be a commonality, like only the amp plug changes it while all the others don't. Or the cable connection brings it in and the amp is the only one that takes issue..

Other than the tried and true stuff, like ground loop blockers or cable xfmrs, a lot of the technique is basically seat of the pants examination and trials. In fact, one thing I rail about is the lack of standardized testing for all equipment with regard to shield currents and ground currents (even neutral currents for two prong stuff, where the neutral currents are below (hopefully) 5 milliamps (Actually, I mean the net current between hot and neutral, what a GFCI looks for.)

It pays to think of it as: where can magnetic fields go through that will induce hum, and where are the fields coming from...many times, you cannot control the generation, but must try to minimize the loops that see the fields.

The star ground design that we have come to live with is the primary reason ground loops give us problems. We believe (inaccurately) that stars are sufficient (as in the safety ground), and as a consequence, pay no attention to the loops caused by the wires going between the boxes. Nor, to the fields generated by the power cords...two prong power cords are very bad if they do not twist. Three prong cords are a little better, but they still couple to one another even though they are twisted.

I am confident that I have provided insufficient verbage to cover a generic problem, it is much easier when one is touching the equipment.

One thing of note: I have used a degaussing coil to look for loops which are sensitive to induced voltages, while this is quite overkill size wise, it is indeed a nice methodology. A smaller coil, say 3 inches diameter, with perhaps 20 to 50 turns of wire, and in series with a 100 watt light bulb (for current limit) is a nice troubleshooting aid. Watch the coil temp, however, as you do not want to burn the insulation.

edit: it is also possible to use a poweramp/oscillator set with a coil and a 4 ohm power resistor, put music (cause sines are so annoying) into the coil, and use the coil to find spots where the music comes out of the main system. Kinda like the fox and hound thing for finding romex in the walls, but at least the sound is more pleasant. When you do this and wave it around any audio equipment, you will see exactly why I do not like star grounds for low impedance equipment. The output lines and power supply lines are doing the exact same thing within the equipment.

Cheers, John

John,

> Nonetheless, your linked page is in error with respect to the blanket assertion of powercords cannot make a difference <

Power cords do not make an audible difference. Now, if a power cord contains an RFI filter built-in, and someone needs that because a solid state light dimmer is buzzing or they have audible clicks or whatever, in that case I could see an audible effect. Likewise for radio station sounds getting into a system. In those cases the interference and noise are obvious, and shielding or filtering are useful. But the claim that a replacement cord can increase clarity and subtle detail or imaging (one of my favorite claims) is just silly. Even more silly is the $1,000 and higher price tags. A good Corcom RFI filter costs about $35.

> (biwiring also, but that's a different day :p ..). <

I can't tell from your two posts if you are agreeing that bi-wiring is a waste or not. I'm quite sure it is a waste.

> It's time to revisit, eh? I'm game. <

Hey, go for it. The worst that could happen is the mods here will toss us both on our ears. :D

--Ethan

Power cords do not make an audible difference. Now, if a power cord contains an RFI filter built-in, and someone needs that because a solid state light dimmer is buzzing or they have audible clicks or whatever, in that case I could see an audible effect. Likewise for radio station sounds getting into a system. In those cases the interference and noise are obvious, and shielding or filtering are useful. But the claim that a replacement cord can increase clarity and subtle detail or imaging (one of my favorite claims) is just silly. Even more silly is the $1,000 and higher price tags. A good Corcom RFI filter costs about $35.

One needs only to review what bad things a power cord is capable of to see that it can indeed make a difference.

First bad thing: depending on it's construction, it can be the cause of hum. Not metal purity or any of those silly things, but by virtue of it's inductance, twist, and ground. The definition of inductance is the relationship between the current within the element, and the amount of magnetic energy that is stored as a result. The higher the inductance (farther apart the hot/neutral), the more energy that is stored within the fields external to the conductors (I neglect the 15 nH per foot internal inductance of all round conductors, as that generally is not changed.)

The more inductance a line cord has, the more it is capable of generating the ac magnetic field which can be trapped by loops in the vicinity, generating voltage via faraday's law. I'll mention the loops a little farther down.

Twist: The intent of a twist is to average out the magnetic field, so that any proximity loop sees a net zero integral flux, ie it averages out to zero. This is great when the victim loop is not twisted. But, when a second cord, say to a source device, is also a twisted tri, the geometry conspires against the averaging.. think about the amp hot and the pre ground...if they have the same pitch, and the ground is at closest approach to the hot somewhere, that closest approach will occur every 360 degrees of pitch...oops.

This is also why mike cables can be sensitive to twisted extension cords, why mike cables can be sensitive to twisted speaker runs. It does require the pitches be integral, or that the area of proximity be little enough that cancellation long term cannot happen.

When a powercord creates the field which causes the hum, the options are: reduce proximity, twist to average out, change the cord to a triaxial configuration, or get rid of the loop that is intercepting.

Now, I've limited the discussion to 60 hz hum. Amplifiers do not limit themselves to 60 hz, haversine draw is odd harmonics. As one goes up in harmonics, the loop gain goes up, again, due to faraday...V proportional to dB/dt...

One can easily envision an audio guy talking about "black background", whereas we would say "lack of haversine inclusion as a result of a ground loop coupled powercord". The hifi guys have a distinctly unscientific set of descriptors, and there is a disconnect to the ele guys..
You are looking only at what can get in via hot/neutral, but that is not the only path..


I can't tell from your two posts if you are agreeing that bi-wiring is a waste or not. I'm quite sure it is a waste.

Biwiring changes the cable loss in a rather interesting way. It doesn't alter the rms loss, but has a really fun product loss that is a zero integral total. In fact, a statement that it cannot alter the instantaneous dissipation conflicts with the first law of thermodynamics.

While it changes the instantaneous dissipation profile, I am unaware of it's audible effects (if any). So even though I've proven the dissipation changes, I consider it of no use for any application I've had. It's much easier to bump the wire guage. If I had to run 5 kilowatts through 200 feet of #2 into a 4 ohm load, then I'd re-think...

We can discuss that another day, lets stick to pc's.


> It's time to revisit, eh? I'm game. <

Hey, go for it. The worst that could happen is the mods here will toss us both on our ears. :D

--Ethan
Hey, I believe we've both been thrown outta classier joints than this..

Honestly, if you and I go at it hot and heavy without cursing or namecalling, why would they toss us??? This is an AV SCIENCE forum after all, and I believe you and I would be using nuttin but science.. Honestly, if we go at it with enthusiasm, I bet we could sell tickets...

Cheers, John

John,

> Nonetheless, your linked page is in error with respect to the blanket assertion of powercords cannot make a difference <

Power cords do not make an audible difference. Now, if a power cord contains an RFI filter built-in, and someone needs that because a solid state light dimmer is buzzing or they have audible clicks or whatever, in that case I could see an audible effect. Likewise for radio station sounds getting into a system. In those cases the interference and noise are obvious, and shielding or filtering are useful. But the claim that a replacement cord can increase clarity and subtle detail or imaging (one of my favorite claims) is just silly. Even more silly is the $1,000 and higher price tags. A good Corcom RFI filter costs about $35.

> (biwiring also, but that's a different day :p ..). <

I can't tell from your two posts if you are agreeing that bi-wiring is a waste or not. I'm quite sure it is a waste.

> It's time to revisit, eh? I'm game. <

Hey, go for it. The worst that could happen is the mods here will toss us both on our ears. :D

--Ethan

I think (although I don't have the technical know how to say for sure) that bi-wiring can be shown to make a difference at least mathmatically. Dr. Greenman ("Morbius") says the same thing, but they both don't claim it is audible. I think they claim it "might" be audible. Then again there might be a "Big Foot" I can't prove there is not. Also, it gets into the whole DBT's that have been done are flawed.

One needs only to review what bad things a power cord is capable of to see that it can indeed make a difference.

First bad thing: depending on it's construction, it can be the cause of hum. Not metal purity or any of those silly things, but by virtue of it's inductance, twist, and ground. The definition of inductance is the relationship between the current within the element, and the amount of magnetic energy that is stored as a result. The higher the inductance (farther apart the hot/neutral), the more energy that is stored within the fields external to the conductors (I neglect the 15 nH per foot internal inductance of all round conductors, as that generally is not changed.)

The more inductance a line cord has, the more it is capable of generating the ac magnetic field which can be trapped by loops in the vicinity, generating voltage via faraday's law. I'll mention the loops a little farther down.

Twist: The intent of a twist is to average out the magnetic field, so that any proximity loop sees a net zero integral flux, ie it averages out to zero. This is great when the victim loop is not twisted. But, when a second cord, say to a source device, is also a twisted tri, the geometry conspires against the averaging.. think about the amp hot and the pre ground...if they have the same pitch, and the ground is at closest approach to the hot somewhere, that closest approach will occur every 360 degrees of pitch...oops.

This is also why mike cables can be sensitive to twisted extension cords, why mike cables can be sensitive to twisted speaker runs. It does require the pitches be integral, or that the area of proximity be little enough that cancellation long term cannot happen.

When a powercord creates the field which causes the hum, the options are: reduce proximity, twist to average out, change the cord to a triaxial configuration, or get rid of the loop that is intercepting.

Now, I've limited the discussion to 60 hz hum. Amplifiers do not limit themselves to 60 hz, haversine draw is odd harmonics. As one goes up in harmonics, the loop gain goes up, again, due to faraday...V proportional to dB/dt...

One can easily envision an audio guy talking about "black background", whereas we would say "lack of haversine inclusion as a result of a ground loop coupled powercord". The hifi guys have a distinctly unscientific set of descriptors, and there is a disconnect to the ele guys..
You are looking only at what can get in via hot/neutral, but that is not the only path..



Biwiring changes the cable loss in a rather interesting way. It doesn't alter the rms loss, but has a really fun product loss that is a zero integral total. In fact, a statement that it cannot alter the instantaneous dissipation conflicts with the first law of thermodynamics.

While it changes the instantaneous dissipation profile, I am unaware of it's audible effects (if any). So even though I've proven the dissipation changes, I consider it of no use for any application I've had. It's much easier to bump the wire guage. If I had to run 5 kilowatts through 200 feet of #2 into a 4 ohm load, then I'd re-think...

We can discuss that another day, lets stick to pc's.


Hey, I believe we've both been thrown outta classier joints than this..

Honestly, if you and I go at it hot and heavy without cursing or namecalling, why would they toss us??? This is an AV SCIENCE forum after all, and I believe you and I would be using nuttin but science.. Honestly, if we go at it with enthusiasm, I bet we could sell tickets...

Cheers, Johnhey, how much should all that good construction of a power cord thingies you talk about cost? (let's say for a 6 foot cord, using what you know and things you can buy on the Internet)

One can easily envision an audio guy talking about "black background", whereas we would say "lack of haversine inclusion as a result of a ground loop coupled powercord". The hifi guys have a distinctly unscientific set of descriptors, and there is a disconnect to the ele guys..
This is quite so. I note though, in the various postings I've read around the web that no mention is made of things like reduction in background noise, hum, or whatever. To my mind this has become one of the buzzwords like expanded soundstage, rhythm, pace, timing, and all those other subjective descriptors that far more likely have their origin in self-delusion.

I recall Morbius saying the same thing Randy but when asked to quantify this is in some way - to put a face on it if you will - he is silent. To my mind, this is just another example of trying to tackle the insignifant many rather than the significant few. OTOH, this could be an example of the feminization of the male population manifesting itself in matters related to audio. It's like the equivalent of breast creams, makeup, sundry beauty products or ingestibles that are purported to do certain things. There should be an eqivalent posting like, 'The claims of this product have not been evaluated by the FDA.'

hey, how much should all that good construction of a power cord thingies you talk about cost? (let's say for a 6 foot cord, using what you know and things you can buy on the Internet)

A perfect cord will not transmit and will not receive. A triaxial construction fits the bill, with hot center, neutral braid over that, and a safety ground shield over that. The hot /neutral set will not have an external field (effectively, of course..nothing's 100%), and any current which flows through the external braid safety ground will not transmit into the neutral or hot, as there is no magnetic field inside a cylindrical conductor.

The big issue I have is current derating. The hot conductor is thermally hidden from the environment, so must be derated accordingly. For example:

A #8 hot, with a 10 degree C rise, runs at 20 amperes. At 35 Degree rise, it'll be close to 40 amperes. But that is ampacity of a single wire. Derating for 16 to 30 conductors in a bundle (somewhat like a triax in theory), is .5. So a #8 wire is probably ok for 20 amps in this config. This set rely's on the insulation integrity of the #8 wire.

The neutral braid can be #12 or #14 depending on what insulation you use over it. Heatshrink over this to lock it down.

The ground braid must be sized at least #14, I'd recommend #12. After all, it's safety..

Overcoat optional, I'd recommend it though, to prevent contact to any chassis.

This is only one part of the solution. If you use 2 or three of these in a star ground configuration, you still have ground loops. But now, any intercepted flux will be from external sources...unfortunately, the romex in the wall is one such beast, both the system feed, and others that pass in the night. In my old condo, the compressor romex feed was inside the wall my stereo was against, it caused a subwoofer pop at turn on before I figured out to wrap the IC around the sub's power cord back to the amp.

To get rid of loop size, I would daisy chain the power. This may not be very practical in some cases.

Of course, if you do not have any kind of ground loop type problems (hum or sound alteration), then this newfangled cord design will not do a darn thing. It's not magical, but can only help reduce a coupling issue if one exists.

Cost?..should not be expensive at all.

Belden 9888 is a 50 ohm triax, with a #12 center conductor, a #12 equiv inner shield, and a #13 (about) outer shield. Personally, I'd get this stuff and strip it down to use the shields, as I do not know if the 9888 is capable of 20 ampere operation long term, the center conductor isn't big enough IMHO..

I also do not know if it is to code to cut conductors off a #8 to fit inside a plug, and I do not know if a triax powercord in itself can meet code.

Given the uncertainty in a triaxial being to code, I cannot recommend anybody build or use a cable of this type. If a manufacturer chooses to do so, I absolutely recommend it be subject to UL approval prior to sale.

Cheers, John

This is quite so. I note though, in the various postings I've read around the web that no mention is made of things like reduction in background noise, hum, or whatever. To my mind this has become one of the buzzwords like expanded soundstage, rhythm, pace, timing, and all those other subjective descriptors that far more likely have their origin in self-delusion.

I've seen postings about background noise, and hum, and lots of "whatever". If a coupling exists between the poweramp cord and the inputs via ground loop coupling, it only happens when the amp pulls power. So an offensive loop doesn't do much when the music is not playing, but will show up when there is a signal to mask the effect. A confounding influence.. One must note, that if this effect is apparent in the TESTING LAB when an amplifier is being evaluated, the test setup is broken. Any engineer would figure out why the amp is testing bad, and fix the external problem. In the home, not too many know to do that if a hum is not apparent..How many engineers out there have had to use a 3 to 2 pin isolator to disconnect the scope ground for a measurement??

There are many "delusional" parts to high end out there, but I am not convinced that it all is. Rather, I am sure that a lack of consistent descriptors, tests, and standards cause no end of communication problems for things which are real.

To me, the perfect example happened when I sent a speaker wireset to a gentleman to evaluate. While about 8 ohms in impedance, it was about #14 awg equivalent. His description of what occurred to the soundstage was rather good, and started me down the path of localization, relative localization, and the characterization of image location as a function of ITD and IID.

Cheers,John

We likely have and do read different areas. As to your story, I can counter where a friend of mine brought some Cardas PC and asked me if I'd hook it up so he could evaluate it. He noted many of the terms I'd mentioned. The only thing was, I faked the switch. And...? Further, if the signal masks the effect, and I'll grant you that it may be subtle and likely measureable, if it's inaudible, then where's the blackness?

We likely have and do read different areas. As to your story, I can counter where a friend of mine brought some Cardas PC and asked me if I'd hook it up so he could evaluate it. He noted many of the terms I'd mentioned. The only thing was, I faked the switch. And...? Further, if the signal masks the effect, and I'll grant you that it may be subtle and likely measureable, if it's inaudible, then where's the blackness?

Counter?? Tis not a debate, actually. Expectation bias is certainly a real thing, we are humans after all. I've not defined what has been measured, just reported on a term and what I interpret that term to be.

Further, if the signal masks the effect, and I'll grant you that it may be subtle and likely measureable, if it's inaudible, then where's the blackness?

As I said, it's my interpretation of what could possibly be going on...I've made no assumption as to the reality of the effect, just what the term could be meaning.

I've come across pa equipment that has a distinct hum when power goes to the speaker..the setup was soooo bad, that the inrush current charging the supply could be heard as a tail on the vocals. The amp itself was fine, but the setup was not. Being a building paging system accessed by phone, nobody cares..

Another, I had an old Aaron-gavin eq, and it produced hiss in proportion to the BASS voltage level. Push a 20 hz sine in, and the modulated hiss could be heard in the tweets.. But during music, I don't hear it...actually, I didn't care, as it met the need at the time... But I wonder what term an audiophile would use to describe the effect????

Cheers, John

My misunderstanding then, John. Once again, the vagaries of communicating in not real time. I wasn't saying that I've never read posts about hum, just that I've not seen an issue remedied with a PC. Of course, there are two-pronged PC's with a 3 prong IEC. Go figure.

My misunderstanding then, John. Once again, the vagaries of communicating in not real time. I wasn't saying that I've never read posts about hum, just that I've not seen an issue remedied with a PC. Of course, there are two-pronged PC's with a 3 prong IEC. Go figure.

Sorry, my fault for not being clearer. I have read of "wonderful things" having been cleared up by anything from home depot wire, to extremely expensive line cords.

While I do not necessarily believe the ad copy of the expensive cord manu's, I know that we on the whole, do not address ground loops in a rigorous fashion. This lack of rigid procedures is a window for so much pseudo-science to enter.

ps. That hum query.., I hadn't even considered that it could be emanating from the xfmrs themselves..interesting.

Cheers, John.

Well, he did say it was coming from the xfmrs. It'll be interesting how that one shakes out. Would you also check for a loose tranformer?

Well, he did say it was coming from the xfmrs. It'll be interesting how that one shakes out. Would you also check for a loose tranformer?

Probably not. He said when the receiver was booting, the hum changed..I can't see how the receiver could physically affect the toroids w/r to being loose...but who knows...

Since the receiver caused a change, I was thinking about the house ground/neutral integrity. My house neutral holds up the two hots from the pole, and I've seen this steel neutral disconnected from the house neutral elsewhere, leaving the water pipe ground as the only ground reference for the house wiring. A very dangerous thing if the water pipe connection corrodes sufficiently. Old houses generally don't have the second rod in the ground near the meter pan. Checking neutral to safety ground at the outlet isn't much of a check I'll admit, but if there's a voltage there, he needs the system checked..

Cheers, John

What's an acceptable differential?

What's an acceptable differential?
Hmm..

#14 is 2.73 milliohms per foot. Figure 100 feet to the panel box, and 15 amperes max.

The ground is not supposed to carry current, so should not have a significant drop.

15 times .273 is 4 volts. If that kind of voltage is present, all is not well in OZ.

I remember some panels have separate ground and neutral busses, and I don't know how legacy panels were allowed to be wired, so I don't know if there is a possibility that a lost neutral from the pole would allow the neutral point to stray from the ground one.

Measuring neutral to ground is the easiest test I could think of. Doesn't mean that it was his problem. I just checked one of mine, it read 117 millivolts ac.

I also tried DC on the AC line, but the meter (a fluke 77 mk III) refused to provide a reading (don't try this at home, lord knows what other meters may do, like blow up??)

Cheers, John

John,

One needs only to review what bad things a power cord is capable of to see that it can indeed make a difference.
I have never been talking about "bad" or broken components. I'm talking about a perfectly competent stock AC power cord that costs less than $5. There is no way to "improve" on that since a good power cord already does what it's supposed to perfectly well - deliver AC power efficiently to a device. Unless the load is 30 amps and the wire is 26 gauge :D it will work fine.

depending on it's construction, it can be the cause of hum.
How can one 3-wire cord have less hum than another? Wait, don't answer that. Here's the real issue:

The claims made by these snake oil vendors are based on magic, and on the premise that the improvements in clarity can be heard but not measured. This is pure hogwash. If one cord is able to deliver AC power "better" than another, then the improvement can be easily measured at the line level or speaker output connections. This is all I care about, and all I've been addressing.

Twist: The intent of a twist is to average out the magnetic field, so that any proximity loop ...
I'm also not considering badly shielded signal wires in proximity to an unshielded power cord picking up 60 Hz interference. The correct solution for that is move the wires, not waste $1,000 on a new power cord.

Biwiring changes the cable loss in a rather interesting way.
Interesting to you maybe but not to me. :D Again, this is silly nonsense where believers claim all sorts of improvements that cannot possibly be real. If bi-wiring can make an audible improvement then it can also be measured. It kills me when the believers rave about how dramatic the improvement is. It's almost never a subtle change, it's always night and day. "Even my wife noticed" is a common line.

--Ethan

The real reason wives notice and comment is that they're desperately hoping that you'll stop your silliness, stop spending money foolishly, and get you to pay some attention to her. Then she can spend money foolishly!

John,
I have never been talking about "bad" or broken components. I'm talking about a perfectly competent stock AC power cord that costs less than $5. There is no way to "improve" on that since a good power cord already does what it's supposed to perfectly well - deliver AC power efficiently to a device. Unless the load is 30 amps and the wire is 26 gauge :D it will work fine.

It is certainly possible to improve on a stock power cord. I've already detailed how,I detailed the transmission mechanism, the reception mechanism. This is not rocket science, it is tried and true engineering. You are stuck on definitions. I do not claim that a better cord delivers better power, which is the crux of your argument...stop claiming that please, as I am in complete argreement with you on that point.

How can one 3-wire cord have less hum than another?

Please re-read what I have stated. Ampere's law details the magnetic field associated with a current, Faraday's law of induction details the voltage that is created by a loop of conductor that traps magnetic flux lines. Variation of the transmission geometry of the power cord and variation of the reception loop of the ground will cause variation of the ground loop currents.

Wait, don't answer that. Here's the real issue:

The claims made by these snake oil vendors are based on magic, and on the premise that the improvements in clarity can be heard but not measured. This is pure hogwash. If one cord is able to deliver AC power "better" than another, then the improvement can be easily measured at the line level or speaker output connections. This is all I care about, and all I've been addressing.

Your assertion that power cords cannot make a difference is in error. I have pointed out how it is in error, and have fully described the mechanism responsible, provided some troubleshooting hints to find the coupled loop, and several method for removing the problem.

Again, I am in complete agreement with your statement regarding magic based solutions as foisted upon us by some vendors. But you are throwing the baby out with the bath water...perhaps acceptable on your side of the sound, but not mine...(don't make me swim over there..) ;)

I deal with these types of problems a lot at work, but my power cords vary from the stock 14 guage computer monitor type, to doubled up 500 mcm three phase 480. You learn a lot when you have to troubleshoot these field/loop issues while measuring magnetic fields on sensitive equipment.


I'm also not considering badly shielded signal wires in proximity to an unshielded power cord picking up 60 Hz interference. The correct solution for that is move the wires, not waste $1,000 on a new power cord.


Again, we concur in that 1K for a power cord is silly. Recall, however, that ground loop hum is not restricted to badly shielded signal wires. And do not forget that coupling is not limited to 60 hz, but increases in proportion to the stimulus frequency. That is, in fact, why the old style light dimmers were the biggest offenders, as they did not have slew limiting on the triac. Signals of that rate of change, if shunted at the amp IEC input, would radiate like an SOB. Man, what difficulties they gave. :eek:

re:biwire
Interesting to you maybe but not to me. :D Again, this is silly nonsense where believers claim all sorts of improvements that cannot possibly be real. If bi-wiring can make an audible improvement then it can also be measured. It kills me when the believers rave about how dramatic the improvement is. It's almost never a subtle change, it's always night and day. "Even my wife noticed" is a common line.

The silly claims are of no interest to me. Nor, the dramatics associated with such.

Using one wire to feed a branch network typical of a speaker crossover, introduces a modulation of the wire dissipation which is proportional to the product of the split signals, it does not alter the rms dissipation, and it apparently is devious enough to hide from fft analysis (most likely due to the zero integral product of the multiplication).

It is a difference, period. I do not know if it alters audibility, and quite honestly, do not worry about it.

It may alter the ITD/IID parameters responsible for localization perception, but again, with the current program material available today which destroys real ITD/IID relationships, there is nothing out there that I'd want to listen to while attempting to discern image locations and relationships. I'm just as happy listening to Inna Gada Da Vita as I am Spring.

Cheers, John

Ps...perhaps you should pass my assertions by Doug..I believe he will understand my "gibberish" and concur..

pps...for you younguns, Inna gada da vita was a song by Iron Butterfly...it had the drums and organ on one channel only, lead guitar on the other, and vocals and bass centered. Interesting to listen to on headphones..Spring is of course, Vivaldi.

pps...for you younguns, Inna gada da vita was a song by Iron Butterfly...it had the drums and organ on one channel only, lead guitar on the other, and vocals and bass centered. Interesting to listen to on headphones..Spring is of course, Vivaldi.I am old so I saw them live back when that song was popular (I guess it is still popular in some circles). The Butterfly opened for the Dead.

Figured I'd include a drawing....gotta have a drawing...

This is a simple drawing I did back in 2004. It depicts the physical mechanism responsible for coupling between the amp draw current and the input ground loop.

(Pay no attention to the fact that the AC lines to the transformer bear a resemblance to a barefoot person with a large derrier. :eek: ..)

Note the asymmetry I introduced into one leg of the power cord. If you extend that completely so that it duplicates the green groundloop, you form a one to one transformer, the worst possible case..

I depict two levels of coupling. First, the total loop that hits on both the ic shield, and the ic center conductor. Shield currents will attempt to reduce the center voltage as a result of reaction currents, so it partially works...but look at inside the amp and source, the blue hatched area...that is a sore point even for balanced equipment, as chassis currents (or shield currents which are passed through a pc trace to a star ground internally) can be responsible for generation of error signals at the output. Somebody here (either speco or sprung) linked to a guy that uses a transformer/rectifer scheme to force shield currents into balanced equip as a troubleshooting aid of the design. But they detail only IR drop involvement, whereas I have depicted magnetic coupling involvment..both exist, which dominates is of course, determined by the physical design of the equipment.

Two levels of error pickup will occur, first order which is proportional to frequency, noted as Iloop, and second order proportional to frequency squared, noted as Vil.

Of note also is the factors K1 and K2 are small...and the smaller the better.

The battery powered soucre is in there as a ground isolated signal source, used to force the amp to draw current from the line. Monitoring of Vin will detect any coupling of the system which is due to the line cord geometry.

Cheers, John

I think some of the consternation here is that John's interests lie primarily in what's different when discussing power cords or biwiring for example. Being exposed to scenarios that are rather unique, John's found that he can effect desired outcomes (elimination of extraneous signals and waveforms) in most cases by applying what he knows from his studies in electrical theory. In some cases the application may be wrapping, in others it may be orientation, and in others still it may be considering how the power cord is made and choosing something unique. Now, speco also has rather unique experiences and they lead him down different paths using alternate solution sets to achieve his goals. I'm sure many remember the old adage, "There's more than one way to skin a cat." Indeed, that is what we find here.

John, I think, because of his experiences and mathematical knowledge, tends to look at some of the issues in a theoretical sense. He generally tends to stop there. Much like Morbius seems to do. The reason I think this is causing some friction is because others are looking beyond this to the issue of audibility. This is especially so when juxtaposed with many of the purported 'improvements' (they do always tend to be improvements!) when someone swaps out their stock cord for a Shunyata, an Elrod, something else.

A concern by some is that if John makes a statement and just leaves it at that, that others will take this as a proof that their personal experiences have validity because of what's said. That I imagine is what has vexed some over at Audioholics. After all, often a statement or data is presented by individuals and companies in such a context pr manner to support a product when in fact, it does not because it needs to be framed correctly. For example, consider those companies who offer super tweeters and use the work of researchers who have close mic'd a trumpet or something and found there is energy way out there. Not only is there energy, but probes in the brain respond to it. Unfortunately they don't tell you that a response is not hearing. It's a response. They don't tell you that were you to be sitting in a theater, these ultrasonic frequencies wouldn't make it that for or would be severely attenuated. They don't tell you that the microphones used or anything else doesn't respond up there and is arbitrarily truncated by the recording engineer. Instead they float a paper and who knows what you'll think. Or believe.

Or consider the work of nobel laureate, physicist Brian Josephson. A brilliant man. He also thinks that all the reports about psychics, talking to the dead, and all that other stuff can be related somehow to matters of physics. Quantum mechanics and all that other good stuff. Now, he hasn't vetted the data. But, he thinks that millions of people can't all be wrong.

Anyways, experiences are wonderful but not all, and I'd hazzard to say most aren't the reason because of something special that's been done. Like a new power cord. Or some mpingo dots. Or tuning blocks. Or lifting your wires up off the ground.

I have no problem with what John says. I respect him and I respect speco. I just see them coming from things from different ways. I don't think it's right that John should not talk about differences. That's not how science and the advancement of knowledge works. John can't help it if people misinterpret his statements or use it incorrectly to bolster something they've heard. John is simply coming from this differently and stopping where he chooses to.

Regards and a good Memorial Day. Let's give thanks to the men and women who've died and will die in the future so that a$$holes like us can argue about matters. Their courage and sacrifice trumps anything I've got to offer.

Chu and John,

others are looking beyond this to the issue of audibility.

Yes, this is all I have been discussing. Not whether this magnetic effect or that inductive reactance can be measured at the equipment end of the power cord. But whether the use of a "better" power cable can affect what comes out the loudspeaker terminals. That is all that matters.

--Ethan

Chu: Well stated, hope your weekend went well.


Yes, this is all I have been discussing. Not whether this magnetic effect or that inductive reactance can be measured at the equipment end of the power cord. But whether the use of a "better" power cable can affect what comes out the loudspeaker terminals. That is all that matters.

--Ethan

We concur, it is indeed audibility that is the bottom line.

With powercord yada yada, I have indeed heard differences, and again, it isn't rocket science. By judicious "massaging" of a powercord, I personally have been able to reduce or increase both hum and noise. And, it did not involve bad interconnects, bad equipment, or bad powercords. It was a result of the e/m environment in which the system was being used. Speco uses equipment which had been designed to reject the environment, and what he uses meets his need, that is all that is important.

My needs are a tad more demanding, requiring at times, novel and very strange solutions.. I applied some of those strange solutions to a very harsh environment, and did so successfully using rather cheap single ended equipment.

Hum caused by ground loops is the last, and largest level of powercord involvement, and one so annoying that everybody stops and fixes it when it happens. Noise like pops and clicks, are the next level. The third level is the amp draw power (which is a modulation caused by the music) getting into the input loop, masked by the music. The first two are trivial to hear, the third has a confounder.

That is where the next level of work begins. Anecdotal accounts of this level of involvement go unheeded by most engineers (who should not), and as a result, the field is wide open for pseudoscience and snake oil explanations. (If you cannot provide them water, they will drink the sand.)

It is not MY presenting the mechanisms which provides fodder for the snake oil people, rather it is the silence of the engineering community at large which is responsible for that hole in our understanding. If you wish to blame me for anything, blame me for setting a fire under the engineer's derriers, they have work to do. I have presented the mechanisms responsible for powercord coupling, I have presented the dissipation mechanism difference caused by biwiring....both are fully grounded in Maxwells theories and basic EE theories. There are two possibilities..ignore them, or use them as a basis for advancement.

My difficulty with Ethan's "white paper/rant" (I didn't know what to actually call it) :confused: , is that for both powercords and biwiring, a blanket statement denies any and all effect, which is of course blatently incorrect for powercords, and possibly in error for biwiring..

Cheers, John

Would you please elaborate more upon the third, perhaps providing examples?

Would you please elaborate more upon the third, perhaps providing examples?

If the system is such that the amp draw is getting back into the input terminals (either the IC ground or the ic center conductor), It's very hard to hear it, the music interferes with the attempts. Without a test setup to look for it, audio types are really just left with random trial and error. My twist/loop stuff is a good start for what to try, but the listening has such problems.


What is needed is a way to isolate the coupled signal from the audio signal, to actually measure any involvement..

Here is a test which is sensitive to the haversine component of the pc ground loop, if the amp causes the problem, this is one way to spot it. (note, this test doesn't look far into the amp chassis, but mainly the fundamental loop pickup caused by the external wires. If there is coupling between chassis ground loop currents and the signal chain within the poweramp, you have to look at the output signal.


Watttasec, file's too large...ah, here we go..

Cheers, John

LOL, I haven't gotten there yet today. I feel like the guy in that joke who reads the obits every day to see if he's still alive. I guess I'm not! :D

One thing that shocked me in that thread was when someone pointed out that discussing Double Blind Testing is not allowed. Say what?! But it gets worse. As the thread at the appropriately-named Tweaker's Asylum has evolved over the past few days, I've been involved in another science-versus-belief thread at Steve Hoffman's forum. Guess what? At that forum you're not allowed to discuss objective versus subjective observation.

It kills me that the believers are so insecure in their position, and they know they don't have a leg to stand on logically or technically, that all they can do is ban certain topics and/or certain people.

I was also banned at Audioholics for the same thing. AH is usually well based in science, but Gene and Clint who run things there have their own belief system that sometimes gets in the way of common sense. In that case I was banned for daring to question the claims of Audyssey for their room "correction" system. I know I can be a bit of an overbearing know-it-all some times. :D But in this case I was polite and stuck to the facts. After about five pages they knew they couldn't refute any of my points, so they just banned me.

Cowards! :D

--Ethan


LOL I thought talking about pm or presidential politics, was a forbidden subject, but Hi-Fi home cinema, come on you got to be kidding me.:D

LOL, I haven't gotten there yet today. I feel like the guy in that joke who reads the obits every day to see if he's still alive. I guess I'm not! :D

One thing that shocked me in that thread was when someone pointed out that discussing Double Blind Testing is not allowed. Say what?! But it gets worse. As the thread at the appropriately-named Tweaker's Asylum has evolved over the past few days, I've been involved in another science-versus-belief thread at Steve Hoffman's forum. Guess what? At that forum you're not allowed to discuss objective versus subjective observation.

LOL. Clearly, AVSForum has spoiled you. AA and SH.tv are notorious for their 'ostridge'-like stance towards not just DBT, but any science-based argument that seems to case a dim eye on 'audiophile' beliefs.
(I see that your Audioholics ban didn't last through the end of '07..but it looks like you haven't posted there since September.)





I was also banned at Audioholics for the same thing. AH is usually well based in science, but Gene and Clint who run things there have their own belief system that sometimes gets in the way of common sense. In that case I was banned for daring to question the claims of Audyssey for their room "correction" system. I know I can be a bit of an overbearing know-it-all some times. :D But in this case I was polite and stuck to the facts. After about five pages they knew they couldn't refute any of my points, so they just banned me.

Cowards! :D

--Ethan

Didn't realize you were banned at Audioholics. The editors there are a bit schizophrenic. They tout themselves as a no-BS site, yet they mix hard-science articles with 'reviews' of gear that are as subjective as anything in the print audio press. And they do shut down some discussions that should be continued, when it doesn't go 'their way'. Still, there are some very informative posters there -- e.g., mtrycrafts, WmAx, Chu, even this jneutron
guy :D

My understanding of biwiring is a direct result of that, which would never have been the case had I never discussed anything on forum. Do you believe a presentation to AES would be received on biwiring?

Pigs will fly first..

A series of DBTs showing under what conditions it's audible, or not, might help those pigs sprout wings. That's been a consistent lacuna in your presentation
if I recall correctly.




btw, I do not use biwiring. I do not consider it practical for my needs.

Cheers, John


Again, in my recollection, these discussions of your biwiring ideas always comes down to this dead-end: its audible effect, if any, seems unlikely to be significant with normal musical material. Please correct me if I'm mistaken.

OTOH, this could be an example of the feminization of the male population manifesting itself in matters related to audio. It's like the equivalent of breast creams, makeup, sundry beauty products or ingestibles that are purported to do certain things.

No jpeg to go with this post? I'm disappointed, Chu. ;)

No jpeg to go with this post? I'm disappointed, Chu. ;)

I was hoping for that breat cream application with directions, picture:D

Wow, this is an old thread!

I see that your Audioholics ban didn't last through the end of '07..but it looks like you haven't posted there since September.

As far as I know I'm still banned. What's so stoopid is a few months later I had an opportunity to test the Audyssey system, and wrote THIS (http://www.realtraps.com/art_audyssey.htm) article proving that I had been right along along. I emailed a link to the guys who run AA with a very nice note. Do you think that made any difference? Of course not! I'm still banned. :D

--Ethan

A series of DBTs showing under what conditions it's audible, or not, might help those pigs sprout wings. That's been a consistent lacuna in your presentation if I recall correctly.

I present holes in current dbt methods which do not consider localization as well as statements that current dbt methods do not find differences..

Again, in my recollection, these discussions of your biwiring ideas always comes down to this dead-end: its audible effect, if any, seems unlikely to be significant with normal musical material. Please correct me if I'm mistaken.

In my application, as well as ANY PA type venue, I consider any effect of no consequence making me double the amount of wire I carry.. I cannot say the same in a sweetspot environment.

Cheers, John

How small is that sweetspot, John?

And no, I won't post pictures that relate to the feminization of males. That's just too weird for me.

How small is that sweetspot, John?

A tad smaller than a 450 seat venue.

I played a B'day party last spring, had a speaker pair at least 40 feet apart, angled about 160 degrees apart when standing center dancefloor. When playing canned mp3's, I found that I could find the sweetspot easily enough. But it was so small, any head translation caused the image to slew rapidly away from center. Outside that small area, imaging was not worth a darn.

So why would I double the wires on the chance that 1...it makes a difference, and 2...that some goofball geek intends on standin in the middle of the dance floor listening for the sweetspot??:confused: (Note: I pretended to assess the "quality" of the music, so that I didn't look like that goofball geek..mp3 at 128 taint exactly, hi def...)

And no, I won't post pictures that relate to the feminization of males. That's just too weird for me.

Um, I think he was talkin bout cheesecake type pics, not beefcake..

Cheers, John