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In Reply to: No, but it can screw up timing... posted by Al Sekela on April 10, 2006 at 08:37:46:
Al,Thanks for the info. This makes sense, Now I need to find an I/C that can take the benefits of transparent and add the "bass weight" back into the audio chain.
Any thoughts about HGA Silver Cables?
Follow Ups:
IME, Teflon is a good, non-smearing insulator for audio cables. Silver's performance depends on how the wire was drawn and what treatments were done to it after drawing to smooth the surface. Silver is very soft and the drawing operation causes surface tearing. Each manufacturer has its own proprietary processes for polishing and/or plating the drawn wire to restore a smooth surface. I don't know where HGA sources its silver wire, so I can't say whether it is better or worse than its competitors.Braiding is another proprietary aspect of cable construction. A particular braid design can reduce inductance without increasing the capacitance too much, but it can also make the cable more susceptible to internal acoustic resonances.
Once the materials and mechanical aspects have been optimized, remaining differences among cable models have to do with their electrical resonance properties. Silver and Teflon are very low-loss materials with wide bandwidth capabilities. This makes cables made from them susceptible to strong RF resonances. It is difficult to dampen the electrical resonances on unshielded cables without affecting the dielectric properties. Several of the reviews on audioreview.com comment on brightness, which could be a result of RF resonances.
The higher-cost HGA cables have the little wooden blocks on them. I don't think these blocks contain low-pass filters, but I don't know for sure.
.
Silver, and silver-plated copper, wires have a reputation for brightness. Even though the conductivity of silver is only somewhat higher than copper, many audiophiles believe silver is excessively bright.In my experience, this folk wisdom comes from RF noise. Any audio cable terminated with mismatched impedances and without significant loss mechanisms is a good RF resonator.
This is similar in concept to an organ pipe, where a slight energy input of white acoustic noise from turbulent air stimulates a strong resonant tone, whose frequency and harmonic structure are determined by the speed of sound and the length of the pipe. Substitute electrical noise for the turbulent air, and the speed of signal propagation within the cable for the speed of sound, and you have the behavior of undamped cables. Any noise source, whether it is radiated from external sources, or carried along with the signal, will set up strong electrical resonances in an undamped cable. Since the speed of propagation is comparable to the speed of light, the frequencies involved are around the UHF band for typical cable lengths.
We cannot hear these frequencies directly, of course. What we hear is the consequence of this electrical noise getting inside the electronic equipment. Wherever it encounters a nonlinear element, such as a dirty contact or a transistor, the noise will mix with the audio signal, similar in concept to the way a radio receiver mixes a radio frequency tone with the tuned radio signal to retrieve the modulated audio information.
The RF noise mixed with the audio signal produces spurious audio tones. These create the impression of 'brightness,' as well as coldness and sterility in the midrange. "Ruthlessly revealing" is another common description for the results of RF noise pollution.
In my experience, applying materials that damp the RF resonances in cables, and filtering the sources of RF noise, go a long way towards eliminating brightness, coldness, and artificial enhancement of treble, detail, and air. More true detail is revealed when the cables are quiet.
Because the processes used to apply Teflon cause corrosion of copper, there is not much wire available that is pure copper coated directly with Teflon. Thus, the properties of the wire insulation are confounded with the choice of conductor material. Since Teflon has less dispersion at radio frequencies than other common insulators, it may be the case that this notion of silver being excessively bright is actually a result of less RF loss in the Teflon insulation, and ability of Teflon-insulated cables to support higher levels of RF resonance. This is just speculation on my part. I do know that my Teflon-insulated, silver-plated copper wires make wonderfully neutral sound.
Hi.If design/built properly, Ag & Ag flated OFHC pure copper do NOT sound "bright" even insulated with Teflon. Given adequate seasoning -
breaking-in, they sound balanced & neutral.This is my hands-on experience for years as I design/build, use & supply Ag & Ag plated OFHC copper ICs & power cords to audiophiles who all love them bigtime even listening to them for the first time. They sound better better with run-in time.
EMI/RFI is everywhere all over the space surrounding our audio gears. If these noise sources are strong & located close enough,
e.g. wireless PC routers, cell phones, switching power supplies commonly uesd nowadays in PC monitors, labtops, plasma/LCD panel TVs, your audio equipment will become targets of RFI invasion.Power cords, ICs & speaker cables, being exposed outside of the equipment, can be ready receiving antennae to pick up those unwanted
EMI/RFI noises, regardless of steel, copper, silver or gold.Now it is a matter of matching or MISmatching of the free space impedance (377 ohms) to the impedance of cables or cords in qustion.
Nowadays, most audio amps are pretty widebanded, say up to 200KHz,
these noises would be amplified & can be intermodulated into
the audio spectrum if the ICs or speaker cables match impedance with the free space impedance of the noises.Such RFI intermodulation will make the music sound hazy, losing details & dynamics.
Of course, there are effective & affordable ways of dismatching the free space impedance to reduce RFI, hence restoring good sound.
So where you get such "resonance" theory on RFI?????? I want to know which textbooks you retrieve from. Or simply your "speculation" or hearsay??
Also how Teflon can cause "corrosion of copper, blah blah ?
I've using my DIYed Telfon insulated Ag & Ag plated OFHC pure copper for years. I am yet to detect my ICs & power cord deteriate sonically due to your alleged "corrosion' by Teflon.
Buddy, another example of hearsay or imagation from you, again?
c-J
"So where you get such "resonance" theory on RFI?????? I want to know which textbooks you retrieve from. Or simply your "speculation" or hearsay??"Do you understand that electrical waves travel on cables as well as through free space? That it takes finite time for a wave to travel from one end of a cable to the other? That this travel time will generally be different than for the same distance in free space?
Do you understand that cable impedance changes wherever the conductor spacing or insulator composition change? That traveling electrical waves are partially or fully reflected at impedance mismatches?
Apparently you do not understand these things, since cable resonance seems to be a deep and dark mystery to you. Your understanding of RF noise in audio systems is incomplete.
What data do you have in support of your assertions that cable resonance is indeed an issue for audio?Or, are you basing all you speak of on anecdotal evidence and speculation?
Cheers, John
And not in public domain. Sorry.
I've seen this used to test long lines, you return a "blip" wherever there is an impedence mismatch... so sya you have a two mile run of communications wire, you originate a pulse and then watch the echos, you should only get one echo at the termination, if there are other minor blips returning before the end blip you may have cable flaws.... it's pretty much a clear demonstration of termination and cable length effects...here's a jave applet so you can play with this concept:
http://www.eecircle.com/applets/018/TDR.html
Anyway.... the ONLY way TDR could work is that conductive materials are subject to internal reflections... the practical issue is that audio cables are too short for most testing arrangments...
I think that the TDR phenomena clearly show that energy reflections between impedence shifts (termination, solder joints) are a real phenomenon that few manufacturers confront directly, except perhaps MIT and Transparent...
all of the possible resonant modes of the stuff at either end of the cable, and how audio frequencies may be modulating this mess, nor how modern devices may be capable of amplifying the residues... isn't that a large part of why Spectral engineered super high bandwidth gain circuits, effectively so they would pass through whatever HF-RF crap rather than acting as a selectively reflective wall... the entire Spectral philosophy appers to be that it is better to allow energy at all scales to freely move from one end of the sytem to the other rather that have local reflective effects... then it became MIT's engineering problem to very carefully manage impedence shifts at the end of the chain and on the ICs, something that would be a disaster with a simplistic ferrite deflector. Others, incuding HP, have claimed that Spectral actually sounds much better with network-less conductors like Nordost... my hunch here is that maybe the Z-cable products that use the ERS RF couple-and-drain method may work as well or better... less junk sitting on the line itself.
I had not thought of that before, and I don't have insight into Spectral's design philosophy, but it makes sense that circuits with LINEAR behavior in the RF will not be mixing RF noise with the audio signal.You are right that electrical noise is either reflected or absorbed. Reflecting the RF noise, whether from shielding or a low-pass filter, only sends it to where it may do unexpected harm.
besides being crystal boundary free, the van den huls by far have the nicest "deep inner voice" of any IC I have ever owned or heard... yes they have other limitations, but having lived with the killer midrange of carbon it is hard to listen to any other material, except the Cerious... I also am now suspecting that carbon has much lower HF/RF ringing and accomplishes this with much greater elegance than any network solution possibly can.... all metals sound zingy and obscured now....
The self-resonance fundamental frequency of a meter of audio cable is around 50 MHz, which is well within the capabilities of even old HP (before Agilent) gear.
The best equipment in the world can be used incorrectly by anyone, test results can be misinterpreted.Articles can be written by "names", and yet be pure garbage.
It would have been nice to have peer review of this "data".
Nothing is learned otherwise..that's my issue here Al..not you. Sorry if I come across strong, but your actions and those of your "friend" are sub standard, shall we say?
Cheers, John
So...Everything is an rf resonator.
Rf is everywhere.
All audio systems are connected by wires which are always rf resonators. And all audio systems are affected by rf, which is received by the resonators.
I could show you the data...but then I'd haf ta kill ya..
Or, trust me, I know what's best for ya..
You need this product, because ""it's"" everywhere..I have the data to prove it, but...you wouldn't understand it anyway, just trust me.
sheesh.
A better explanation would have been, you hear such and such, and when you treat it like "this", it clears up. even without measurements.Personally, I would recommend that before you ask someone "which one of Maxwell's equations don't you understand", you be ready to support your "unsubstantiated" claims with something other than "my dog ate my homework".
Claims of audibility are just fine..anecdotal evidence, fine..lack of data to support a claim of audibility...still, just fine..that is consistent with the intent of this forum.
But if you wish to claim rf resonance is causing all this trouble, show us more than a cop out.
Cheers, John..
"A better explanation would have been, you hear such and such, and when you treat it like "this", it clears up. even without measurements."You don't read many of my posts, do you?
Have I ever said that RF resonance is causing all this trouble?
RF resonance in audio cables is a large part of how they contribute to the details of RF noise troubles in an audio system. Anyone with even a mid-fi system can prove it for themselves with a few simple and cheap experiments. However, reducing resonances in cables does not address the root causes, which are the noise sources.
Al: ""RF resonance in audio cables is a large part of how they contribute to the details of RF noise troubles in an audio system. Anyone with even a mid-fi system can prove it for themselves with a few simple and cheap experiments. However, reducing resonances in cables does not address the root causes, which are the noise sources.""Yah, like I'm gonna believe it..:-)
Data, dude..data..
You make claims..testable claims..
but, no tests? not public domain???sheesh, I woulda been more creative..
Cute..
Simple experiments are never that.
If it were, life would be so much easier.
What's the Q of a power cord? Input power, peak, transfer, what..
Unsupported claims are just what they seem..Cheers, John
Yes, he has made some "claims", but he does have an extensive posting history, and it would behoove you to read some of it via the handy search engine here at the Asylum.His stance is not a wholly unreasonable one, and anyone with a modicum of understanding should be able to pick up the gist of what he is talking about, without requiring some sort of certification of existence to even think about it seriously.
If you read some of his previous posts, both here, and on Tweaker's, you would see that some of the experiments he suggests are indeed simple and easy to perform.
Oh, I know you want it handed to you on a "silver platter" {maybe it would sound smoother if it were a copper platter? ;-) }, but those kinds of demands remind me so much of a lazy naysayer, not worthy of YOU to be playing that game. Tsk, tsk.
Jon Risch
JR: ""
Yes, he has made some "claims", but he does have an extensive posting history, and it would behoove you to read some of it via the handy search engine here at the Asylum.""Some claims?? try searching his name and resonance. The only thing that doesn't rf resonate is silly putty.
Claims can be anecdotal, as in something observed, with an attempt to explain what is heard using what is known.. Or, they can be measured, which means there is data. Or, they can be observed, and an attempt to measure has been done, again, data. Or, attempts to modify the system to remove the effect can be done, with observation again used to determine effectivity.
All are possible and valid methods of determination, some more rigorous than others.
In my years here, I have watched Al, and find him to be very knowledgeable and intelligent. As such, he lives with a higher bar. As do you and several others. My expectations of him, you and the others are considerably higher than most.
One of those expectations is the requirement of civility. Asking another which of Maxwell's equations don't you understand, IMHO, is beneath Al. I would not have entered into a dialogue here if not for that. Yes, he was responding to someone who is also civility-challenged. And yes, it is difficult deciding how to deal with such posting behaviour..but I consider Al to be above that..
JR: ""
Oh, I know you want it handed to you on a "silver platter" {maybe it would sound smoother if it were a copper platter? ;-)""Indeed, the platter material is of concern...:-)
JR: ""
but those kinds of demands remind me so much of a lazy naysayer, not worthy of YOU to be playing that game. Tsk, tsk.""I am not playing a game. I consider the "tests" he alludes to as inaccurate, inappropriate, setup entirely wrong, and results horribly misinterpreted. The initial premise, the testing, the conclusions are all poor, misplaced, out of whack. The tests were not performed scientifically, and confounding influences were not condisered at all.
Now, my having stated my "unproven assertions", where do we stand????
NO test setup, no test description, no test parameters, no test results, nuttin, nada. No peer review, no critical eye to look for possible test error..
Is this what you consider a discussion forum??? It's true, I tested it, but....you can't see the results??
No, that is not a discussion.
A discussion would be much better. Not deriding another for not knowing something, and then hiding the "something" from the public..
CJ is not without fault, considering his posting nature, and Al just reacted.
Still playing that idiotic naysayer bs, huh Jon? I consider you to be above that crap..apparently I am incorrect?
Cheers, John
Al knows quite a few inventors and manufacturers. In my few years knowing and working with Al, he will sometimes refer to a proprietary situation in which he is keeping a confidence for someone who is working on or has a process he'd like to protect. His wording in such cases is pretty similar to what you reacted to in one of your posts above.I've never heard him say those words otherwise. So my take when I read it was that it impinged on one of those areas where he felt duty bound to keep that confidence. NOT that he couldn't tell you or didn't have something to back it up. And he's usually shown me what he has to back it up in terms of real auditory experiences (not data, which would be wasted on me as I'm not at his EE level).
If you are so sure that Al is overstating his actual knowledge, then you could say so civilly and simply and ignore him if he persists or if you continue to disagree. I'm not so sure as you appear to be about this, because I've been working with his ideas and found them to be useful, but that's just my experience. Obviously, you've found him not just a blowhard here too, or you wouldn't laud him as you have above.
So how about either the benefit of the doubt or just doubt it and let it go?
Jon has asked that we back off of the DBT and similar demands for "proof" on this forum many times. In fact, that seems to be one of the rules for this particular forum. And unless I'm mistaken, the moderators have asked us all to cool down...
bartc: ""
Al knows quite a few inventors and manufacturers. In my few years knowing and working with Al, he will sometimes refer to a proprietary situation in which he is keeping a confidence for someone who is working on or has a process he'd like to protect. His wording in such cases is pretty similar to what you reacted to in one of your posts above.""No, that is incorrect. Maintaining the confidence of proprietory information is not the same thing as asking "which one of maxwell's equations don't you understand"..
The gist of cheap jack's questions (although I agree his demeanor via his typing was "piss poor") was, "how do you know that rf resonance is indeed occurring in the conditions of a typical system setup". The answer to that "question" should not have been the backhanded derogatory remark over cj's knowledge of e/m theory...a remark guaranteed to instigate more flames instead of tempering..
Protecting another's proprietary data is entirely admirable, and should have been the first statement, not the last.
bartc: ""If you are so sure that Al is overstating his actual knowledge, then you could say so civilly and simply and ignore him if he persists or if you continue to disagree. I'm not so sure as you appear to be about this, because I've been working with his ideas and found them to be useful, but that's just my experience.""
At no time have I stated that Al is overstating his knowledge. Please do not make that mistake again. While I may not agree with all, I still consider his posts a must read.
bartc: ""
Jon has asked that we back off of the DBT and similar demands for "proof" on this forum many times. In fact, that seems to be one of the rules for this particular forum. And unless I'm mistaken, the moderators have asked us all to cool down...""I never ask for dbt. First, it is against the rules of this forum..
Second, I consider dbt's to be flawed. In essence, it fails to address long term localization reconstruction, which human brains are required to do, but cannot, on an instantaneous level, as short term audibility tests require. In this assertion, I wholeheartily am in agreement with JR.
Asking for supporting data is perfectly acceptable, even within this forum.. Asking it of a non technical person is not fair, of course, but Al is well beyond that, so can easily field the question..
I was miffed at his slapping cj over the understanding of e/m, as well as dissapointed that any and all data is "secret", but that's the world of business, which I understand..
The guys I work with don't slap me around because of my rudimentary understanding of Maxwell's equations, perhaps that is too much to expect here?
BTW, very nice post...a pleasure..
Cheers, John
.
"I do know that my Teflon-insulated, silver-plated copper wires make wonderfully neutral sound."He does not disrespect SPC off-the-cuff like some folks do. What is your beef? Cheers
(BTW, I also find use for SPC cables in my systems)
.
Most Teflon-insulated copper wire has silver or nickel plating applied before the Teflon insulation is extruded onto the wire. A cable vendor explained to me a long time ago that this was done because the Teflon extrusion process was too harsh to use on bare copper.The URL link below explains that silver is used to coat stranded copper wire because standard tinning on the strands would melt at the Teflon extrusion temperature. Stranded wire would be, in effect, soldered together into a solid bundle.
Bare copper oxidizes rapidly at higher temperatures, as anyone who has tried to solder it would know. Unless the Teflon extrusion process were done in a reducing atmosphere (hint, this would add a lot of cost to an industrial process), bare copper wire coated with Teflon would have a robust oxide layer on its surface, and be difficult to work with in an industrial context. This is not to say that it can't be done, just that this is why it is not done very much.
The platings are only needed with the TFE teflon, which has to be extruded at a higher temperature than the FEP teflon, the higher temps free some ofm the chlorine/flourine, which can attack the bare copper, while the silver or nickel is more ressitant to the corrosion.The TFE teflon _can_ be extruded under very high pressure, which allows a lower temperature to be used, and thus, bare copper, but the continuous length possible with this process are limited, due to the amount of TFE plastic material that can be loaded into a ram press for the high pressure extrusion process, and of course, it is very expensive to do.
FEP teflon hardly ever causes bare copper corrosion, unless the manufacturing process literally goes out of control.
According to theory, TFE teflon should have a slight advantage over FEP teflon, BUT, it has not been verified under controlled conditions, due to the problems with creating identical conditions for a set of wires using both insulations, and identical conductors.
In the real world of silver plated TFE teflon versus bare copper FEP teflon, neither is perfect, but the flaws and issues of the FEP+bare copper seem to be less irritating long term than those of the TFE+plating. Of course, some folks prefer the sound of the TFE+plating, but my own opinion is that it is not quite as neutral or accurate overall, at least with real world signal sources.
Jon Risch
Thanks for the clarification, Jon.The performance of high-end audio systems is always a balance of physics and taste. Gross flaws due to uncontrolled physical effects can be ameliorated, but taste simply has to be respected. A bottle of Russian River Pinot Noir may be tainted with trichloroanisole from an infected cork, but even a pristine bottle may not be to a particular person's taste if the grapes or the winemaker's methods emphasized the wrong characteristics.
My experience with silver-plated wire is based on military-surplus material. I've tamed the RF noise problems and am happy with the sound. However, this wire is only used for speaker cable in my system; my interconnects use another proprietary wire, and I use power cords made with stranded copper wire. It is certainly possible I would not like the sound of silver-plated copper wire in my interconnects.
Just want to add that a need of plating has been true of PTFE Teflon which has a harsher extrusion process than FEP Teflon which seems to be kinder to bare copper wire. FEP Teflon insulated bare copper has become a more common insulator (I don't know of any corrosion issues). Anyone have more info to share? Does Cardas use PTFE or FEP to insulate their Teflon insulated bare copper wire?
Hi.You are talking to someone who is approved supplier of design/built
fire-rated low capacitance instrumentation cables used in civil aircrafts, e.g. Boeing.I am now working with a flighttest engineer of a worldwide major aircraft builder on a new project for using fine instrumentation cables inside the aircraft wings, as contrary to the normal practice of laying instrumentation cables inside the plane body.
Tinned copper conductors in foam Teflon (FEP) insulation are specified mainly for the moisture corrosion precaution inside the wing voids. "Copper corrosion" by Teflon is news to us.
Also major cable suppliers, like Belden, make tons of LAN cables & instrumentation cables with BARE copper insulated with Teflon FEP.
Obviously, these big boys know better than your cable vendor.May I suggest you to study more whatever relevant subjects before you open your mouth next time. I don't have all the time to set the record straight for you so as not to mislead our readers.
c-J
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