All cables follow the relationship LC=1034*EDC. EDC is effective dielectric coefficient. For a coax or low aspect ratio stripline, the EDC is exactly the dielectric coefficient (relative) of the insulator. Commonly used plastics have a DC of 2.7 to 3. Foamed dielectrics can go down to 1.05. Times microwave has also taken their larger coax down to that level using a spiraled dielectric spacer between core and shield like their LMR900 heliax.
When the conductor spacing is increased, the EDC increases to incorporate the loss of magnetic field containment. Typical zips run an EDC of about 5, worst case 10.
While I can appreciate the work you have done, I do not see any effort to actually understand how a cable impedance impacts audibility. I understand what a VC does in a gap during velocity and acceleration, as well as the flux dragging and eddy current issues which can impact soundstage image, quite beyond the audio "guys" I have seen so far.
I sigh at the attitude both sides have despite not actually understanding the actual technical stuff. My preference is one of trying to understand all the technical things...some don't wait for that knowledge but still argue.
In my work environment, the most difficult problems I am called in to solve are what I call "hybrid" problems. Multi-disciplinary problems, problems which cross lines of expertise.
I am really good at hybrid problems, as I have no real expertise in any discipline.. 😊 Just ask anyone...
John
When the conductor spacing is increased, the EDC increases to incorporate the loss of magnetic field containment. Typical zips run an EDC of about 5, worst case 10.
While I can appreciate the work you have done, I do not see any effort to actually understand how a cable impedance impacts audibility. I understand what a VC does in a gap during velocity and acceleration, as well as the flux dragging and eddy current issues which can impact soundstage image, quite beyond the audio "guys" I have seen so far.
I sigh at the attitude both sides have despite not actually understanding the actual technical stuff. My preference is one of trying to understand all the technical things...some don't wait for that knowledge but still argue.
In my work environment, the most difficult problems I am called in to solve are what I call "hybrid" problems. Multi-disciplinary problems, problems which cross lines of expertise.
I am really good at hybrid problems, as I have no real expertise in any discipline.. 😊 Just ask anyone...
John
Referring to your Lady-Fidelity.pdf document, was an interesting way of misusing network analysers and you wonder why the return loss results were all over the place.
Pages 131-134 is a description of not attempting to measure the impedance of a wall socket outlet but more akin to an experiment of electrolysis with two electrodes connected to mains power via a isolation transformer.
The document is basically pseudo science, and your use of chickens on page 211 was rather, lets say questionable.
Every crazy project has only two outcomes. Pass or fail. Sometimes it may lead to new things. There might new invention for those weak hearing to have induction lines etc. Some might find they can hear those extra high frequency after changing to these new physics cables. May be for some spy activity as the cable is painted on the wall like a strip. Who knows? I want to call this a snake cable, but won't for now. Is it because snakes do not shed copper skin?
Enjoy the experiment. Regards
Enjoy the experiment. Regards
@LFQA
One thing your measurements leave out are the motor effects in cables as described in the AES papers. They found some correlation between modulation of capacitance with voltage in line level cables, and modulation of wire spacing geometry in headphone cables due to magnetic force caused by current flow. Although the effects are small, apparently some people can hear them under some conditions. Other people have reported similar results, a difference in cable sound depending on mechanical stability of the conductors.
Regarding winding cable on a spool and charging it up with 10kV, perhaps that could permanently alter the cable, say, by charging up the dielectric with enough voltage to leave some trapped charged (something similar to the trapped charge in an electret), the extent of which partially depends on the how much the cable is mechanically stressed by its bend radius on the spool. Once a cable has sufficiently been altered mechanically and or electrically to make it effectively a non-uniform line then of course it could be possible to measure directional effects, depending on the measurement method. In any case, I would probably consider such a cable to be damaged. Probably not a good choice of cable to use. Particularly so if the process that altered is not carefully controlled so as to produce a desired alteration. If its just sort of an accidental change in the cable, again it would probably be best described as damaged.
So it still seems to me that choosing to measure some things and not other things, then trying to correlate what was measured with what is heard is probably not likely to give consistent or reliable prediction of cable sound. OTOH when measurements are done first, a prediction of sound is made next, then blind listening tests are done last, it is only by such as sequence of events that we can determine the explanatory value of a hypothesis. The more generally it works reliably, say, with a wide variety of cable constructions, geometries, dielectric materials, and manufacturing processes, then the more useful it would seem to be as predictor.
One thing your measurements leave out are the motor effects in cables as described in the AES papers. They found some correlation between modulation of capacitance with voltage in line level cables, and modulation of wire spacing geometry in headphone cables due to magnetic force caused by current flow. Although the effects are small, apparently some people can hear them under some conditions. Other people have reported similar results, a difference in cable sound depending on mechanical stability of the conductors.
Regarding winding cable on a spool and charging it up with 10kV, perhaps that could permanently alter the cable, say, by charging up the dielectric with enough voltage to leave some trapped charged (something similar to the trapped charge in an electret), the extent of which partially depends on the how much the cable is mechanically stressed by its bend radius on the spool. Once a cable has sufficiently been altered mechanically and or electrically to make it effectively a non-uniform line then of course it could be possible to measure directional effects, depending on the measurement method. In any case, I would probably consider such a cable to be damaged. Probably not a good choice of cable to use. Particularly so if the process that altered is not carefully controlled so as to produce a desired alteration. If its just sort of an accidental change in the cable, again it would probably be best described as damaged.
So it still seems to me that choosing to measure some things and not other things, then trying to correlate what was measured with what is heard is probably not likely to give consistent or reliable prediction of cable sound. OTOH when measurements are done first, a prediction of sound is made next, then blind listening tests are done last, it is only by such as sequence of events that we can determine the explanatory value of a hypothesis. The more generally it works reliably, say, with a wide variety of cable constructions, geometries, dielectric materials, and manufacturing processes, then the more useful it would seem to be as predictor.
I placed order for a rotary air flow equipment that can move air from one end to other end at 60 Cubic meters per minute, with 5 level flow control and a start stop enable control built with triple 120 degree spaced air flow dispensing mechanism.
And I received a 3 blade ceiling fan with a regulator. Word jargon is to confuse people and make them believe that something is so good and unmatched.
Regards.
And I received a 3 blade ceiling fan with a regulator. Word jargon is to confuse people and make them believe that something is so good and unmatched.
Regards.
I've been thinking about making my own foil cables; to reduce capacitance, I was thinking about starting of with PTFE tube ( sold for 3D printers ), wrapping copper foil ( slug repellant tape, leaving on the waxed paper backing ) in a spiral ( both to make a foil tube, and to alow some flexibility ) then threading it into another tube ( I've got some silicone rubber tube, but it's VERY grippy, threading anything down 2 meters of it could be impossible ), and having two twisted together, one positive, one negative. I think I might just be lazy, and have 4 lengths of solid core cat5 wired as star quad.
Congratulations.
VERY few people are even aware about that, even less design speakers considering it, which is MOST important.
In my field, Guitar speakers, it is vital.
Musicians are not into measuring, of course, not even into datasheets or reading parameters, BUT they have well developed ears, by definition, and instantly detect speaker to speaker differences when acceleration differs between units.
In part it explains the (well deserved) reverence for 50s technology "Alnico speakers". (basically old Jensen speakers, "P" series : P6/8/10/12/15 in 3 voice coil sizes: R/Q/N".
Magic properties are assigned to Alnico itself, and convoluted theories are made up to "explain" it, although in principle the voice coil only "knows" what field it´s floating in, not what creates it, while the real deal lies in 50´s type build materials and construction.
Typically "minimum copper" use (small voice coils, only gap depth windings, so short thin wire involved= lowest mass possible), wound on minimum mass possible paper formers, glued with low residue (low solids content) nitrocellulose adhesive, a.k.a. "speaker cement", all together making for lowest mass possible for each voice coil geometry.
Add to that minimum amounts of light "speaker cement" gluing VC to a light thin cone and you have an unbeatable combination.
Mojo? Fairy dust? Magic?
Not really, IF you reproduce those parameters and designs today you can reach same results.
Now since the early 70´s Technology has advanced step by step improving power handling , from early 10-12-15 W RMS , to , say, 100-150W but lost quality along the way, first by introducing strong but heavy Epoxy adhesives, then going from Paper to Kapton or Epoxy-fiberglass formers.
And stronger but thick-heavy cones.
Again, not magic at all, everything measurable.
And no mystery or misapplied theories: plain Physics 101 (which for some around sounds like 4 letter words 😉 ), simple: F=M*A so A=F/M
Steadily, motor design has focused in increasing Force: large diameter, longer windings, huge magnets, thick plates to carry magnetism to gap with minimal losses, more copper in the gap, stronger adhesives, thicker stronger cones, etc. which no doubt have given us the modern high power speaker, but step by step lost old school "finesse"
Again, not an idle word, everything measurable and backed by construction type.
Not so sure about flux dragging, I always considered it part of flux interaction (VC vs gap ones) although yes, voice coil is moving perpendicular to gap flux; eddy currents are real whenever a conductor moves in a magnetic field but area involved is small, only within each (thin) wire section.
Now don´t start me on aluminum formers 🙄
🤣 🤣🤣
I remember an 80´s PA speaker ad bragging of "multiple parallel planes organic composite material" walls, "reinforced with STEEL pins" .... which actually meant plywood walls nailed together 🙄
Mind you, those cabinets held well, thanks God they also used good glue, internal bracing, etc. , but I always rolled my eyes when reading the ad copy.
When the VC is carrying a hf current, and a lf current is forcing large excursion, the vc field is being dragged across the front plate and pole piece. The eddies in the iron fight the rate of change.
Think of a vc wound on the tip of a long non- conductive tube being held over an aluminum cylinder such that it can be energized by sine, and independently moved with an actuator at the far end. With no current in the coil, the actuator at the far end will see no effects caused by the vc over the aluminum. But if you put current in the vc, the actuator will see the effect of the eddies, it will act as a dampener, dissipating energy.
If the actuator is running 60 hz, and the vc current is 200 hz, the dissipative eddies will be rather complex in nature, not the simple summation of the two effects.
Just had this type of problem at work, an aluminum structure was vibrating horizontally with a magnetic field perpendicular to and passing through the structure. The resultant change in magnetic field was at twice the plate frequency.
John
Thanks.
I was thinking about eddies in voice coil itself, but yes, plates and polepiece are there too.
Mechanically static but if voice coil moves, there still is a relative movement.
I was thinking about eddies in voice coil itself, but yes, plates and polepiece are there too.
Mechanically static but if voice coil moves, there still is a relative movement.
So you're basically saying, for someone like me, who tickles drivers with 1/2 watt per channel ( measured at amp power supply ) ,car speakers should be avoided like the Plague, and I should be looking at cheap paper " boom box " type full range drivers, with their tiny coils/air gaps, or even using 4 small drivers, for even lighter cones/coils; that matches with what I hear, low power paper drivers have more life and subtle detail.
Car speakers are abominations.
Many Excellent FR speakers are like I described, just check their specs or construction methods and you´ll see.
Not cheap tiny AT ALL but Classic construction.
Notice that some modern speakers follow what I suggest, even not recognizing it:
* some good FR units (I don´t want to say say "respected" because that´s a much abused and devalued word) get low mass and higher acceleration by the trivial way: small and light themselves, say 6" to 4" and sometimes even 3"....
One example, simply because it was mentioned a couple days ago, the Visaton BG17
https://www.visaton.de/en/products/drivers/fullrange-systems/bg-17-8-ohm
* 6.5" ... check
* light thin cone ... check
* light tiny 20mm diameter voice coil, only 7mm length winding ... check
They most certainly use modern materials (Kapton? Epoxy?) to get that 40W rating but small physical dimensions partly compensate that.
And I bet a classic paper voice coil and adhesives would be killer there, leaving everything else the same.
* notice: "Moving Mass 6.5 grams" 🙂 ... check
And they are not even trying! 😉 , it´s an inexpensive (not "cheap") speaker, meant for sale to general Public, not tiny Audiophile market, and yet it performs surprisingly well:
A Full Range focused manufacturer can make a 10" or 12" unit with same or better high frequency results and definitely more extended Bass by following the Classic way.
In fact,a few do.
No strict need for paper and nitrocellulose either, very good coils can be made using Nomex and Cyano adhesives but of course, if you liked "paper", then you are in good company 😉
Many Excellent FR speakers are like I described, just check their specs or construction methods and you´ll see.
Not cheap tiny AT ALL but Classic construction.
Notice that some modern speakers follow what I suggest, even not recognizing it:
* some good FR units (I don´t want to say say "respected" because that´s a much abused and devalued word) get low mass and higher acceleration by the trivial way: small and light themselves, say 6" to 4" and sometimes even 3"....
One example, simply because it was mentioned a couple days ago, the Visaton BG17
https://www.visaton.de/en/products/drivers/fullrange-systems/bg-17-8-ohm
* 6.5" ... check
* light thin cone ... check
* light tiny 20mm diameter voice coil, only 7mm length winding ... check
They most certainly use modern materials (Kapton? Epoxy?) to get that 40W rating but small physical dimensions partly compensate that.
And I bet a classic paper voice coil and adhesives would be killer there, leaving everything else the same.
* notice: "Moving Mass 6.5 grams" 🙂 ... check
And they are not even trying! 😉 , it´s an inexpensive (not "cheap") speaker, meant for sale to general Public, not tiny Audiophile market, and yet it performs surprisingly well:
A Full Range focused manufacturer can make a 10" or 12" unit with same or better high frequency results and definitely more extended Bass by following the Classic way.
In fact,a few do.
No strict need for paper and nitrocellulose either, very good coils can be made using Nomex and Cyano adhesives but of course, if you liked "paper", then you are in good company 😉
Testing cables we included many factors so in order to select cable parameters that could help us understand
what is good and is needed to transmit the signal down a cable.
Low Dielectric constant cables have low permittivity of the static fields.
Distortion of the static fields distorts the magnetic fields and affects the Fidelity of the audio signal.
We use high dielectric constant materials to support the Static fields in a cable.
We had listening tests too with cables already designed - we measured them and learned that we could some-what,
predict a cable design would sound like - Smith Charts are very useful.
Mr. Diamond has very good listening skills and he did most of our Hearing testing.
After a good design, we would send our 'new' Item off to stereophile mag personel
for them to see what hey thought.
Cj
This is my first post, I can identify with this fellow. I was fortunate enough to serve my apprenticeships at a time when an AA was considered a step above the average Joe and by no small margin. In a neighboring state at the time the 8th grade was the end of the scholastic road for many a young lady or man. They started their apprenticeships if they were invited.
Some of the best wood workers in the world are located in that state BTW.
I find the assumption that years in a school room some how equates to being better than, when in reality it is missing the same measure of experience the 8th grader had in the neighboring state. I have met many people that have had 35 one year experiences in their lives. That is not the same as 35 years of experience.
Practical application in the mono/stereo world are at most the first and second year OJT for most mechanics on a 5 year program. Every professional labor employees parts of different skill sets from more rigid and defined information provided by our more informed scholastic counterparts. The smartest guys I knew when it came to electronics had a few degrees in engineering, BUT he also teaches an Automotive class to youngsters. I wondered why? It covers everything he learned, he explained to me. I just laughed as I put another band-aid on my smashed thumb.
As a retired HD master mechanic I worked with a few different Electrical EEs, several civil and sound engineers. That doesn't account for the majority that were into fluid dynamics and hydraulic engineers. They all work with 3 mechanics. I really enjoyed their input but it still boiled down to me, to FIX the broken equipment, not the engineers. Their job was already done. Now does it work and keep working? Can we take the data and see fewer issues. That was their job. If they couldn't the company hired different engineers that could. What is an education worth if it doesn't fix anything, improve or reduce cost? That is what it is worth, nothing more nothing less. Follow the $$$$ that is usually where the problem is. LOL
Stereo stuff is pretty simple, why is a cable so controversial and why do people make stereo gear out to be complicated. IT'S NOT. People sure make it complicated though. 15.8 billion different ears in the world. That is 15.8 billion different ways to hear.
Copper ribbon and good ol tan masking tape work really well. Termination was always the biggest issue. I folded the ends back (doubled the conductor thickness. I cut a U in the copper and solder the U with silver solder. I clean the soldered U and they last over 10 years in the 70s. The tape was still good, but you had to be careful. Nothing turned green, BUT this is a pretty dry climate. NO salty fog within 60 miles or so and the Chlorine pools are across the street.
I'm sorry if I left out "The stuff" that explains it all. I'm a pretty simple fellow.
I sure enjoy the site. I've watched for years, but never posted.
Regards
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@diepiolet
Thank you for posting. Many people never do.
Understand about described experiences with degreed engineers. Also understand about the sorts of things exceptional techs can bring to the table. Only suggestion would be not to draw too many firm conclusions from one's own personal experiences. There are many different engineers and techs in the world. Some might be very different from what someone has experienced so far.
Regarding stereo, it is not necessarily so simple. The basic concept is simple of course. Making it perform as a convincing illusion of soundstage (including the illusion of width and depth) is not so simple however. IME that can get more complicated than we usually try to measure with our commonly used distortion analyzers.
Thank you for posting. Many people never do.
Understand about described experiences with degreed engineers. Also understand about the sorts of things exceptional techs can bring to the table. Only suggestion would be not to draw too many firm conclusions from one's own personal experiences. There are many different engineers and techs in the world. Some might be very different from what someone has experienced so far.
Regarding stereo, it is not necessarily so simple. The basic concept is simple of course. Making it perform as a convincing illusion of soundstage (including the illusion of width and depth) is not so simple however. IME that can get more complicated than we usually try to measure with our commonly used distortion analyzers.
I'm wracking my brain trying to figure that one out. Even tried googling..
Harley Davidson?
Heavy Duty?
Hydraulic Dampeners?
I have the pleasure of working with some of the most skilled techs on this planet.
As an engineer, I have always been very hands on. They learn from me, I learn from them. It's the only way. (or it should be).
While I agree it doesn't require a 4 year degree to do research, it is important to have a base understanding of the topic being worked on. My work at home on a mill and lathe really helps me discuss problems we have at work regarding how to build complex widgits that need to be accurate to tenths of a thousanths of an inch over a 2 meter length. And when I need help with something I am trying to do at home, I have a huge base of experience I can draw upon to answer my questions.
It can be a turn off seeing somebody using the science incorrectly, using the wrong test equipment to get results, and then misinterpreting the results to match an expectation.
I find on occasion I am teaching 30 and 40 year experienced degreed engineers the basics of t-line theory, EMC/EMI fundamentals, skin and proximity effect theory and practice on machines that take 10 minutes to walk around. They are not easy topics, nor are they even taught well in a 4 year degree. And out in the field, it can be really important to understand the fundamentals.
John
The biggest thing is taking very complicated information and making ME or YOU feel like we understand it and are a part of the solution, not just following orders. I have worked with some very good mechanics that could not explain anything. You better pay attention. I've worked with squints that made everything easy to understand but you need to keep them out of the ditch so to speak. Because my work required a level of correctness that many don't need it was and is a way of life for some and not for others.
A stereo repair is pretty simple, the question is the design worth repairing or making better. The only place I find a difference is a piece of gear I would NEVER pay for in 1000 years. 60K DACs and 10K PC. I suppose those test results should be about 99.9999999% accurate vs my poor old Macs I paid 200.00 for in the 70s. Because my old ears and an occasional piece of test equipment come out, it doesn't negate the fact my ears heard the problem, not the test equipment. I just happen to isolate an issue with additional test. EX; a bad or noisy valve for example.
Let me make it simple. I'm all tested out.. LOL When I retired the tools actually jumped out of my hand and into Tool Boxes. Good riddance. The job did not treat me or any other mechanic I know well.
LOL ok I worked on foundational and ground reinforcement equipment. From tieback rigs to tunnel boring support. Bauer and a few of their smaller companies. Liebherr, CAT, JD, Putzmeister, Schwing and a few more supported their equipment on their chassis. Pile drivers, breakers, large diameter boring equipment, super cranes, tunnel boring, trench cutters, HUGE equipment. Not your typical highway equipment.
The electric side of thing can get VERY complicated. CANN buss. 30 different nodes was not uncommon, doing soil-mixing and pressure columns 160 feet deep 3 feet wide. Engineered steel all the way to the bottom. A lot of CPUs keeping thing within that margin of error. The whole time shaking like a Saturn 5 rocket being lit off. Vibration control? You cannot make anything ridged enough in mother nature. It has to move. Huge shocks were usually anchored to the columns and the shocks to the sliding slab on top of that. The Towers were that way. Trench cutters 2 stories tall cutting trenches that held back the Hudson during a serious bombing.
Sound Engineers were the best. Most didn't care what a stereo did. They only care if the freeway noise was going to be in the new hotel lobby they just built on the strip in Vegas. Don't forget the safe in the bottom of every casino either. 70-90 feet below the surface.
Good stereo room I suppose. I only saw the outside, never the inside or the safe door for that matter. Tighter security than the Whitehouse that's for sure. LOL. What a wonderful place to look at in pictures, Vegas. Blood, sand and heat.
Did I mention I don't care to work in Las Vegas. I preferred the phone work, like reset the E-Stop or did you turn the key ON?
I like that work.
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