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Author Topic: cables - facts and fiction  (Read 52216 times)

dcollins

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Re: cables - facts and fiction
« Reply #15 on: February 24, 2005, 11:26:57 PM »

[quote title=dcollins wrote on Thu, 24 February 2005 20:04]
danlavry wrote on Wed, 23 February 2005 14:45


Micro-diode? I never heard of that one but it sounds interesting Smile



They claim that effect for adjacent strands touching...
Quote:


Any other examples of cable BS?  


Too many.

 http://www.enjoythemusic.com/magazine/equipment/1202/bybee.h tm

This one eats 1/f noise for breakfast!

Even RAP was unmoved!

http://www.national.com/rap/Story/0,1562,3,00.html

DC

Bobro

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Re: cables - facts and fiction
« Reply #16 on: February 25, 2005, 04:33:30 AM »

From one of the cable sites...

"Alternating current can shake a wire like a guitar string"

Is that fact or fiction? Seems plausible actually, but highly exaggerated.

-Bobro
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Sahib

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Re: cables - facts and fiction
« Reply #17 on: February 25, 2005, 08:13:55 AM »

Yes it could be true. If it is 10,000VAC applied onto a wire with insulation rating of 1000V which is laid over a wet floor.
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danlavry

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Re: cables - facts and fiction
« Reply #18 on: February 25, 2005, 10:33:05 AM »

Bobro wrote on Fri, 25 February 2005 09:33

From one of the cable sites...

"Alternating current can shake a wire like a guitar string"

Is that fact or fiction? Seems plausible actually, but highly exaggerated.

-Bobro


Guitar strings don’t shake. They vibrate, and the mechanics is well understood. The frequency is proportional to string tension, inverse proportional to length, inverse proportional to the square root of the diameter and there is also a material dependence (a constant). Guitar strings vibrate for mechanical reasons, not electrical reasons.

Of course, if you take the guitar string out of the guitar and lay it on the floor (like a speaker wire), both the guitar string and the speaker wire will not vibrate (or shake), which makes the statement “sort of correct” Smile
Of course one can have an electric current induce eddy currents in a metal conductor, or make a motor turn around, but making an electric motor is a very deliberate design. Laying a speaker wire on a wood or stone (or any non conductive or metallic) floor will not induce vibrations. If speaker wires vibrate, so would the 0.004 inches wide traces on your computer printed circuit board…

The electrical wiring for AC (in your house, place of work, and everywhere) carries a lot of 60Hz energy (many amperes). I wonder what would happen to someone in the building and construction industry if they came up with such a crock, claiming that the wires shake, or trying to sell a "no shake AC wire".  

It would be interesting to know what that manufacturer says about who they go about solving that shake, and if they claim that their cable shakes less then other cables.

Regards
Dan Lavry
www.lavryengineering.com




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danlavry

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Re: cables - facts and fiction
« Reply #19 on: February 25, 2005, 12:10:05 PM »

Look at what I found on the web:

“Silver Sonic wire features advanced winding geometries, which help to cancel out magnetic fields that may degrade sound quality. These advanced geometries effectively enhance performance and transparency.”

Great science! A speaker wire maker eliminates one of the 5 electromagnetic principles. Maxwell is down to 4 equations (not 5).

“Silver Sonic 12 gauge wire carries the lower frequencies. The upper frequencies are carried by 14 gauge Silver Sonic wire - the same as in the critically acclaimed DH Labs T-14 speaker cable.”

Oh great! How do they do that? Maybe they came up with a sub molecular crossover networks for speaker wires Smile Another “possible explanation” is that the electrons inside the 12 gauge wire have more space then the electrons in the 12 gauge, therefore they eat more, get fatter and become too slow and lazy to move fast Smile

“Multi stranded slow drawn oxygen free copper (OFC) wire is heavily clad with high purity silver. …The adroit combination of silver with OFC offers the benefits of the "Silver Sound" characteristics sought after by audiophiles, at much less expense than 100% silver cables. This includes crystal bell-like clarity, sense of "air" and realism, musical detail and speed, and overall delicious musicality”

The operative words are SLOW DRAWN. What will happen if you draw it too fast? Will the electrons go through an emotional trauma and become neutrons instead? Everyone knows that neutrons do not have that bell quality ring and ping  Laughing

“Synergizing pure silver with oxygen-free copper creates a smooth, full bodied sound quality; OFC takes the edge off of the hard bright sound that can be typical of 100% silver cables. Mids are clear, neutral, dynamic, and smooth. Bass is detailed, deep, clean, and tight. Spectral balance is very accurate. This very intellegently engineered design offers genuine high-end audiophile sonic quality for far less cost than competing brands.”

How does OFC detect that there is a “hard edge bright sound”? Too many electrons moving in the same direction? No, that definition means too much current, and we do not want to have current limits. Electrons moving too fast? No, that defines high frequencies, and we do not want to muck with that either. Too much voltage between the wires? Ah, maybe we can short the wires to each other and eliminate the edge Smile

“Tube equipment users will love Silver Sonic Cables, which make a wonderful match. Silver can sound wonderful with tubes, and their low capacitance is great for your equipment.”

In other words, if you are a sucker for BS you are a serious candidate…

Vibration dampening material placed within the jacket greatly reduces detrimental resonances and microphonic effects, which can also smear sound and create harshness.

I understand microphonics at low level signals, typically with DC voltage between the wires (such as for condenser mics). But microphonics on speaker wires?

But at least they do not charge $16000 for a pair of 8 foot wire Smile

Regards
Dan Lavry
www.lavryengineering.com
In times of deceit, telling the truth is a revolutionary act.
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Tomas Danko

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Re: cables - facts and fiction
« Reply #20 on: February 25, 2005, 01:01:08 PM »

Sahib wrote on Fri, 25 February 2005 13:13

Yes it could be true. If it is 10,000VAC applied onto a wire with insulation rating of 1000V which is laid over a wet floor.


...and THAT is why you need to buy them acrobatic cable stands!

Very Happy

Cheers,

Tomas Danko
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Tomas Danko

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Re: cables - facts and fiction
« Reply #21 on: February 25, 2005, 01:19:50 PM »

danlavry wrote on Fri, 25 February 2005 17:10


?Multi stranded slow drawn oxygen free copper (OFC) wire is heavily clad with high purity silver. ?The adroit combination of silver with OFC offers the benefits of the "Silver Sound" characteristics sought after by audiophiles, at much less expense than 100% silver cables. This includes crystal bell-like clarity, sense of "air" and realism, musical detail and speed, and overall delicious musicality?

The operative words are SLOW DRAWN. What will happen if you draw it too fast? Will the electrons go through an emotional trauma and become neutrons instead? Everyone knows that neutrons do not have that bell quality ring and ping  Laughing

But at least they do not charge $16000 for a pair of 8 foot wire Smile



A friend of mine who has a habit of building ridiculously expensive microphones, considered to be some of the finest on the planet, and who is such an incredible source of knowledge while always being extremely devoted to improving on everything surrounding his craft (uh... this guy suddenly starts to sound like someone else who builds beautiful converters, er?) once told me he doesn't use modern "fast drawn" copper.

Simply because if you draw it too fast it might create cracks on microscopical level, and that could lead to a non-perfect result.

And this is why he once found a huge pile, 180 kilo worth, of 7 mm thick copper laid out like a retarded snail going backwards, something like 1918 in the south parts of Sweden. He still uses this, and this also means that there are single stranded (uh, when does it become too thick to be called a strand? Probably way before 7 mm I'd venture) 7 mm cables in his gear, such as mic pre's and power amplifiers. Even for something like a line-level application.

I ain't saying he's got it right. After all, he's got only one working ear. But he is my hero, and the things we do (and sometimes pay) for that high frequency articulation... Wink

Sincerely,

Tomas Danko
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danlavry

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Re: cables - facts and fiction
« Reply #22 on: February 25, 2005, 05:39:36 PM »

Tomas Danko wrote on Fri, 25 February 2005 18:19

danlavry wrote on Fri, 25 February 2005 17:10


?Multi stranded slow drawn oxygen free copper...crystal bell-like clarity, sense of "air" and realism, musical detail and speed, and overall delicious musicality?

The operative words are SLOW DRAWN. What will happen if you draw it too fast?


A friend of mine...Simply because if you draw it too fast it might create cracks on microscopical level, and that could lead to a non-perfect result.

Sincerely,
Tomas Danko



Thank you for your comments.

Since I am not a mechanical engineer, a chemist, or a material specialist I am in no position to argue about fast drawn and or oxygen free copper having better or worse mechanical properties. In fact, as a user of copper wire, I do not care if the copper was drawn or glued or hammered, I do not care if it was heated to 500 degrees or 1000 degrees.

I do care about the mechanical specs such as flexibility, and I want wire that is not fragile.

However, these are not the claims that we heard. In fact I do not recall any statements referring to mechanical characteristics (not that I would believe a single thing they say). Instead the claims are MAKING A CONNECTION between slow drawn and or oxygen free to electrical and sonic characteristics.

So what is your point? I am certainly open to arguments that a different manufacturing processes may yield different characteristics. But it is my business to know the electrical side of the story, and electrically speaking, copper is basically just copper, with very little variation. For example, an 18AWG hard drawn copper yields 6.385 Ohms per 1000ft at 20 degree C, and weighs 4.917 lb per 1000 ft. The same 18 AWG annealed copper yields 6.640 Ohms per 1000ft at 20 degree C, and weighs exactly the same - 4.917 lb per 1000 ft. The difference in resistance is 4%, which is less then the tolerance in wire dimensions (thus in resistance). The inductance is the same for hard drawn and annealed, the capacitance for identical mechanical configuration is also the same.

So given that the conductive material (copper) is virtually the same, one can have it made into solid wire, or stranded wire, round, square, triangle… One can have more cross sectional area or less (which will affect resistance and inductance), one can insulate it with Teflon PVC or other materials (and that will change cable capacitance), one can shoot for more surface area (effecting skin effect at high frequencies)….  

Given inductance L and capacitance C per unit length, the characteristic impedance is pretty well pinned down (square root of L/C) and the propagation delay is also pretty well known (square root of L*C)… Yes the model can be refined a bit to account for high frequency losses (FREQUENCIES WAY ABOVE AUDIO FREQUENCIES)….

Of course there are a number of wire and cable variations and features and many of them have to do with MECHANICAL properties.

Many of the cable makers know that they can not sell someone a very expensive cable on the grounds that it will not break, or that it can withstand 1000 degree C, or that it flexed well. So they “invent” all sorts of “sick theories”, trying to pray on people’s ignorance. It is outrageous for anyone to put a 12 AWG in parallel with a 14 AWG to provide low and high frequency paths.

Who writes such BS? If it is written by a professional EE, it is clear deceit. The other alternative is that the material is written by a non technical type and presented as technical facts. This is still deceitful. What would happen to those guys if they made similar claims for gear sold in the medical field?

Regards
Dan Lavry
www.lavryengineering.com
In times of deceit, telling the truth is a revolutionary act.
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Tomas Danko

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Re: cables - facts and fiction
« Reply #23 on: February 26, 2005, 11:25:47 AM »

danlavry wrote on Fri, 25 February 2005 22:39

Tomas Danko wrote on Fri, 25 February 2005 18:19

danlavry wrote on Fri, 25 February 2005 17:10


?Multi stranded slow drawn oxygen free copper...crystal bell-like clarity, sense of "air" and realism, musical detail and speed, and overall delicious musicality?

The operative words are SLOW DRAWN. What will happen if you draw it too fast?


A friend of mine...Simply because if you draw it too fast it might create cracks on microscopical level, and that could lead to a non-perfect result.

Sincerely,
Tomas Danko



Since I am not a mechanical engineer, a chemist, or a material specialist I am in no position to argue about fast drawn and or oxygen free copper having better or worse mechanical properties. In fact, as a user of copper wire, I do not care if the copper was drawn or glued or hammered, I do not care if it was heated to 500 degrees or 1000 degrees.

I do care about the mechanical specs such as flexibility, and I want wire that is not fragile.

However, these are not the claims that we heard. In fact I do not recall any statements referring to mechanical characteristics (not that I would believe a single thing they say). Instead the claims are MAKING A CONNECTION between slow drawn and or oxygen free to electrical and sonic characteristics.

So what is your point? I am certainly open to arguments that a different manufacturing processes may yield different characteristics. But it is my business to know the electrical side of the story, and electrically speaking, copper is basically just copper, with very little variation. For example, an 18AWG hard drawn copper yields 6.385 Ohms per 1000ft at 20 degree C, and weighs 4.917 lb per 1000 ft. The same 18 AWG annealed copper yields 6.640 Ohms per 1000ft at 20 degree C, and weighs exactly the same - 4.917 lb per 1000 ft. The difference in resistance is 4%, which is less then the tolerance in wire dimensions (thus in resistance). The inductance is the same for hard drawn and annealed, the capacitance for identical mechanical configuration is also the same.



Personally I'm completely with you on this. However, as for my friend I'd say there are two issues touching the matter. The first one is that even if there is only a difference in Ohms of, say 0.01, and this will not make a practical difference there is still a tiny difference in theory. And striving for the ultimate would rule out 'slacking' on that 0.01 value. If nothing else, so that one can claim to have done the best he possibly could.

The second issue is hands down the only sane (and barely at that, I should add) reason for the first issue to ever happen. The issue of cost being taken out of the equation. This friend of mine doesn't care what the final price will be, and in his private universe it's a small price to pay in order to be able to live with himself. Of course, one could start questioning the sanity in that, but hey whatever floats his boat eh...

I like this world a whole lot more whenever I find out about people going way over the top in their aim towards achieving their maximum. Not to be confused with ripping people off by selling them ridiculously expensive cables.

However, outside in real life, these things do not matter. I mean, what's next? Coming to the conclusion that the unit needs to be tilted at a 3 degree angle and never be more than ten meter above sea line in order to operate in its optimal state?

Just put a wooden knob on it, and get rid of that mind-ghost. As some people tend to do.

But if you ask me, I think a not too slow, not too fast, not too thick, not too thin laid down piece of wire will be the best choice.

It's just that it won't be costing a gazillion, and will not serve as an ego-booster nor fill up someone's bank account...

Sincerely,

Tomas Danko
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JGreenslade

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Re: cables - facts and fiction
« Reply #24 on: February 27, 2005, 07:20:38 AM »

I've posted a link to these before, but seeing as we're on to the topic: http://www.solid-tech.net/products/cradle.htm

Taken from the link:
Quote:


Wires are microphonic, and in order to achieve your system's peak performance, it is essential to isolate them from large resonance prone structures - such as the floor!



I'm sold! Is that "wires" in the single or multi strand sense?

I wonder what kind of SPL you'd need to actually induce an audible / measurable signal into a cable? Maybe if it was near the centre of an atomic blast? Do "audiophile" speakers go that loud?

Some interesting products here: http://www.russandrews.com/ Also note the travesty that is the "Wattgate" mains connector. It's interesting that they mention the studio market to be one of their expanding client bases...

Justin
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Sahib

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Re: cables - facts and fiction
« Reply #25 on: February 27, 2005, 01:30:37 PM »

Dan,

I know that this forum is about scientific facts and I am of no believer of voo-doo medicine and snake oil. However, if you think it is appropriate I would like to take this wire issue from just simply slagging-off to a bit of ' what if ' argument. I came across this interview (extract), I have highlighted the significant lines;

......Because Dr. Cabot has dedicated his career to audio measurement, I felt his views might shed some light on the debate between those who judge audio-equipment performance by measurement and those who judge it by listening (footnote 1). During a recent trip to Oregon, I visited Audio Precision's headquarters and asked Dr. Cabot how far measurements go toward describing the sound of an audio component:

Richard Cabot: I certainly believe that if something can be reliably heard—if the person really is hearing it—you can measure it if you know what to measure. But I would not swear that I could, with a simple set of measurements, automatically measure the right things. I would try to do a broad spectrum of measurements. There are a lot of measurements that we haven't figured out how to make yet. We aren't really measuring the right things.

Measurements are often made around what is convenient to measure or what is useful in a design viewpoint to assess tradeoffs in the design. If you are looking at designing some equipment, you go back many years to when people first started doing audio measurements in the hi-fi business. They were battling amplifiers that had several percent harmonic distortion. Harmonic distortion was a measurement that related very well to bias tradeoffs in vacuum tubes and output characteristics of output transformers. Measurements in widespread use today were developed because they were useful in assessing characteristics of what you were designing, not necessarily because they were useful in assessing the characteristics of what you heard. It's extremely rare for anyone to address measurements from the viewpoint of what we hear and work backwards to what it is we need to measure in a device.


My question is. If, for example on a signal or speaker wire there is an audible difference, even if it is very very little and we can not measure that, then how do we reconcile it with our mathematics?

Regards,
Cemal
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Dan Mills

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Re: cables - facts and fiction
« Reply #26 on: February 27, 2005, 03:17:15 PM »

Sahib wrote on Fri, 25 February 2005 13:13

Yes it could be true. If it is 10,000VAC applied onto a wire with insulation rating of 1000V which is laid over a wet floor.


Actually, I have seen this effect, but it is high current (not voltage) that causes it. It is basically a magnetic effect and is seen in large three phase power lines under overload conditions.

I witnessed it in a non overload situation while working in a club that was using strobe flowers which pull fractional cycle pulses of current in the several hundred amp region... I was in the intake room and kept hearing this ticking sound coming from all the conduit! Very strange, as it sounded like something was heating up but I could not find anything running at more then luke warm.

It was only when the second strobe flower kicked in at a slightly different rate that I finally twigged to what was going on.

This is one reason why single core heavy power cables must mechanically secure to resist the magnetically generated forces in an overload situation.

So while it is technically true that AC can generate forces on cables (and that these can become large), it takes a great deal of current to cause a problem in practice.  

Regards, Dan Mills.


 
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danlavry

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Re: cables - facts and fiction
« Reply #27 on: February 28, 2005, 10:25:29 AM »

Sahib wrote on Sun, 27 February 2005 18:30

Dan,

I know that this forum is about scientific facts...

......Because Dr. Cabot has dedicated his career to audio measurement, I felt his views might shed some light on the debate between those who judge audio-equipment performance by measurement and those who judge it by listening...

Richard Cabot: I certainly believe that if something can be reliably heard—if the person really is hearing it—you can measure it if you know what to measure...../b]

My question is. If, for example on a signal or speaker wire there is an audible difference, even if it is very very little and we can not measure that, then how do we reconcile it with our mathematics?

Regards,
Cemal



I certainly believe that if something can be reliably heard—if the person really is hearing it—you can measure it if you know what to measure.

I am glad you quote Dr. Cabot. He is one of the people I respect most!!! Note what he said: His statement begins with "IF someone can RELIABLY hear"…

That is a very important statement. While being very open minded, Dr. Cabot also has some limits as to when one needs to stop being "open minded". If one can reliably hear is the limit. If one comes up with a crock, it is a different story.

One has to remember that being open minded is no license for every snake oil salesman to come up with non scientific theories and deception. One must be sure that the criteria of hearing reliably is met.

After meeting that criteria, one has to find the CORRECT cause, not just make up things!

I do not know if anyone that is as capable as Rich Cabot in the area of testing (and believe me Rich Cabot is also great in other areas). So when it came to the sampling at 192KHz, I did not get into intricate testing issues. All I needed as a basis for my argument is the fact that human hearing extends to say less then 30KHz (or even 40KHz). The rest was just math, iron clad and solid and provable. No one is ready to come forward claiming they are can hear 40KHz (reliably or not) in a double blind test.    

I invited Dr. Cabot to be on my panel (All about AD’s) in the NY AES, 2 years ago. I later heard him as a guest in a Seattle AES meeting. Both times he stated VERY STRONGLY that the experts at the forefront of digital audio originally wished to have the sampling rate at about 60KHz.  

Yes, one has to be open minded to things we do not know. But one has to draw a line, and stop mucking with what we DO know. We know that 1+1=2. We know that Nyquist was right. We know a hack of a lot about cables and material conduction, and capacitance and so on.

Yes, someone can come along and teach us something new, even about cables. But it has to be based on real science and engineering, with reliable demonstration. Not about unbelievable crock. Let's face it, many of the cable stories both about how they sound and why they sound better are a huge crock.

Regards
Dan Lavry
www.lavryengineering.com

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Sahib

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Re: cables - facts and fiction
« Reply #28 on: February 28, 2005, 12:46:37 PM »

Couldn't have agreed more, many thanks.

Regards,
Cemal
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ammitsboel

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Re: cables - facts and fiction
« Reply #29 on: February 28, 2005, 03:22:15 PM »

Dear Dan,

In the beginning of this thread i asked this:
Is it possible to scientifically explain the audible differences in let's say speaker cables?

So far i have got this:
Quote:

Obviously cables have resistance, capacitance and inductance. Does any of it matter for audio frequencies? The capacitance matters least; the resistance does not matter much. The inductance seems to have a slightly higher impact, not much but enough to make me wonder why people buy the huge heavy wires with less resistance but higher inductance.

I guess the answer is "marketing".


And this:
Quote:

...electrically speaking, copper is basically just copper, with very little variation. For example, an 18AWG hard drawn copper yields 6.385 Ohms per 1000ft at 20 degree C, and weighs 4.917 lb per 1000 ft. The same 18 AWG annealed copper yields 6.640 Ohms per 1000ft at 20 degree C, and weighs exactly the same - 4.917 lb per 1000 ft. The difference in resistance is 4%, which is less then the tolerance in wire dimensions (thus in resistance). The inductance is the same for hard drawn and annealed, the capacitance for identical mechanical configuration is also the same.


Does this mean that we still don't have the techniques available to measure what the ear have known about cables for about 50 years or more?


Best Regards
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