Why are we going 300 or more directions?


Funny, if you design a hi-speed coaxial cable, the fundamental design is the same. I do mean the same. Physics have honed the basic construct to the same physical design no matter who makes it.

Yes, conductor and shield materials will change some based on the frequency range, but not the design. If you change the basic design, you get worse performance, and not just differentiation (unless worse is your differentiation).

Then we have audio cables. True, audio exist in a frequency range where stuff does change with respect to frequency (impedance drops markedly as frequency is swept from 20 to 20 kHz) but this still doesn't allow willy-nilly designs from A to Z to hold the best electrical ideal.

If there are X number of speaker cable makers, only a small few can be the most ideally right according to physics for audio transmission. What we have is so much differentiation that it is almost humorous.

If "we", as in speaker cable designers, all got in a big room with the door locked and could not be let out till we balanced the design to best effect...what would that cable look like? Why?

Go to any web site and you can't get one-third of the way through before vendors allow misconception to be believed (references to velocity of propagation for instance) that are meaningless in their feint of hand or simply unprovable as to their effect...simply fear you don't have it. For instance, high velocity of propagation allows you to simply lower capacitance, the speed is there, but irrelevant at audio and cable lengths that you use. The signal travels too fast to matter. Signal delay is in the 16ns range in ten feet. Yes, that's 16 trillionths of a second. It's the capacitance folks, not the velocity that you engineer to. But velocity "sounds" exciting.

Audio cable over the years should be under CONSOLIDATION of principals and getting MORE like one another, not less so. I don't see a glimmer of this at all.

The laws of physics say there is a most correct way to move a electrical signal, like it or not. Electrical and magnetic fields have no marketing departments, they just want to move from A to B with as little energy lost as possible. You have to reach a best balance of variables. Yes, audio is a balance as it is in an electromagnetic transition region I mentioned earlier, but it STILL adheres to fundamental principals that can be weighed in importance and designed around.

A good cable does not need "trust me" engineering. An no, the same R, L and C in two cables don't make them the same. We all know it isn't that simple. BUT, the attributes (skin effect and phase responses) that DO make those same R, L and C cables different aren't magic, either.

I've listened to MANY cables this past six months, and it no longer amazes me which ones sound the best. I look at the several tenets that shape the sound and the designs that do this the most faithfully always come out on top.

DESIGN is first. Management of R, L, C, Skin effect and phase. Anyone cam stuff expensive material in a cable, few can DESIGN the right electrical relationships inside the cable. Why be stuck with excessive capacitance (over 50 pF/foot) to get low inductance (less than 0.100 uH/foot) when it's NOT required, for instance. A good design can give you BOTH!

MATERIALS are a distant second to sound quality. They contribute maybe 2 tenths of the total sonic equation in a quality design and ZERO in a bad design. A good design with standard tough pitch copper will exceed a bad design with single crystal cryogenic OFC silver-plated copper. You can't fake good cable design and the physics say so. Anyone can buy materials, so few can do design.

Being different to be different isn't a positive attribute in audio cables. Except for all but ONE ideal design it’s just a mistake.

I've listened to the same cables with dynamic speakers and electrostatic speakers, and the SAME cables always come through with the same characteristics. Good stays good. True, the magnitude of character is different, but the order hasn't moved.

I'm not real proud of the cable industry in general. True transmission accomplishments should reach common ground on explainable principals and that SHOULD drive DESIGN to a better ideal. But, we people do have emotions and marketing.

What do I look for in a speaker cable?

1.0 Low capacitance. Less than 50 Pf / foot to avoid amplifier issues and phase response from first order filter effects where the phase is changing well before the high-end is attenuated. The voltage rise time issue isn't the main reason low capacitance is nice, it's that low capacitance removes the phase shift to inaudible frequencies and doesn't kill amplifiers.

2.0 Low inductance as we are moving lots of CURRENT to speakers. Less than 0.1UH /foot is what you want to see. Good designs can do low cap and low inductance, both.

3.0 Low resistance to avoid the speaker cables influencing the speakers response. The cable becomes part of the crossover network if the resistance is too high. For ten-foot runs, look for 14 AWG to maybe 10 AWG. Bigger isn't better as it makes skin depth management issue too hard to well, manage.

4.0 Audio has a skin depth of 18-mils. This is where the current in the wire center is 37% of that on the surface. The current gradients can be vastly improved with smaller wire (current closer to the same everywhere). How small? My general rule is about a 24 AWG wire as this drop the current gradient differential across the audio spectrum to a value much less than 37%. Yes, that's several wires. Don't go overboard, though. Too much wire is a capacitance nightmare. Get the resistance job done then STOP at that wire count.

5.0 Conductor management. Yes, point four above says more than one wire, many more! And, if you use 24 AWG wire for skin depth management, it can be SOLID to avoid long term oxidation issues. I've taken apart some old wires and it can look pretty bad inside! Each wire needs it's own insulation.

6.0 Symmetrical design. Both legs are identical in physical designs allows much easier management of electricals.

7.0 Proper B and E field management is indirectly taken care of by inductance and capacitance values. The physics say you did it, or you didn't. BUT, you can design in passive RF cancellation if you use a good design, too. Low inductance says that emissions will be low, however, as less of the energy is generating an electric and magnetic field around the wire, thus limiting EMI / RFI emissions.

8.0 Copper quality is finally on the list. It doesn't matter without one to seven! The smaller the wires (infinitely small), the LESS the silver plate will warp the sonics. If the current density is the SAME at all frequencies, then all frequencies see the same benefit. If a wire is infinitely big than the high frequencies will see the majority of the benefit. 20 Hz and 20kHz are at the same current density on the wire surface. But, the gradient difference is too small to matter with 24 AWG wires. If you want silver, let the silver benefit everywhere!

9.0 Dielectrics. Dead last. Why? Because capacitance is driven by your dielectric. If you have the low cap, you have the right dielectric for the design. You HEAR the capacitance and NOT the dielectric per say. True, Teflon allows a lower capacitance for the same distance between wires, thus making lower capacitance. But, if you FOAM HDPE from 2.25 down to 2.1 dielectric constant, it can meet the same cap at the same wall and sound just as good. Careful though, it is now more fragile! It's a trade-off in durability, not sound quality. Teflon isn’t magic. It is expensive.

10.0 This is not last per say as it is CHOICE in design. I do not like fragile cables laying on the floor to be stepped on. Some do. A good cable design should be durable enough to take that late night trip to the TV set with the light low, and then step on your cable by accident. The cable should be user friendly.

Everything above can be calculated by known physics equations with the exception of copper quality on sound. I'll have to hear this on two IDENTICAL cables except wire quality. But, why would a vendor allow you to do that when they can scare you into a more expensive copper? I'll be glad to pony-up if I'm allowed to make the judgement for myself. Or, let be buy it at a reasonable price!
rower30

Showing 14 responses by jneutron

What we were taught in school about t-lines and reflections did indeed discount the possibility of reflections in the audio band for short cables. Unfortunately, that was based on an approximation, one used to simplify the engineer's job. Like the skin effect approximation of the exponential equation, where the depth calculation is good enough as long as you remain within the limits where the approximation is accurate enough. T-lines are the same.

The actual effect short line reflections will have on 1Khz signals for example, is extremely small. 5, 10, even 20 uSec delays on a 1Khz sine is so small that it is ignored in standard work. If I were running a few kilowatts at 1Khz into some load and worrying about delays and losses, I would also ignore ten uSec as well.

Unfortunately, humans have this absurdly powerful capability to discern direction of a sound source at the 1.5 uSec and up level. This level of interchannel time discernment is where the standard engineering techniques begin to fall apart.

The complexity of virtual image localization is sufficiently high, that I always recommend any technical person who wished to consider or argue cables first learn a bit about what humans can hear, as that is really the end result wished..what is audible.

For a low impedance amp feeding a 150 ohm speaker wire to a pure resistive load, the actual current delay at the load will be a function of the line to load match. If load = line, the delay will be exactly the propagation delay, measured in nanoseconds. If the load is very low or very high with respect to the line, it will take a large number of reflections and transits until the load current has settled to 90-95% of the expected value.

Since speakers can vary wildly across the audio band, I would recommend trying to get near the center of the range. It's reasonable to run wires at 25 ohms for example, by using perhaps 5 or 6 independently twisted #18 or #20 awg zips. No specific braiding of rancy stuff, just twiste them independently but make sure polarity is correct at each end.

If you try to go at or below 4 or 8 ohms, you will really have a lot of capacitance in the cable makeup. It has to be noted that capacitance is NOT an issue for any amplifier on the planet as long as the load at the far end matches the cable's characteristic impedance.. But if the load impedance climbs up with frequency, then the amplifier will see significant capacitive storage and may oscillate if the unloading occurs below the open loop unity gain point of the amplifier. The use of a zobel at the far end can prevent the unloading which is the problem.. If your amplifier is marginally stable with a low z cable and high z load, a cable made with a built in zobel will indeed be highly directional.

I do not recommend making the cable lower than the load especially if the load is 4 or 8. My recommendation is to make the cable somewhere in the middle of the load impedance min/max.

ps. are all posts on this site moderator approved, or is this a trial period for bad eggs like me?

jn
GK, I prefer discussing scientific entities. Your statements are not scientifically supported by any test.

If you wish to claim burn in of wires, please provide scientific evidence of such claims.

If you wish to claim cryogenic alteration of either dielectric or conductors, please provide scientific evidence of such claims.

Anecdotal accounts are of no significance as scientific proof. They are useful as a self serving vehicle, but not as proof.

Long time no speak, Geoff. How have you been, how are you doing? I hope all is well with you.

jn
The skin effect numbers cited are incorrect. In the audio band, it is necessary to use the bessels for accurate numbers, the exponential approximation is incorrect.

All t lines obey the simple equation LC =1034 DC when the t-lines are constrained, such as coax, high aspect ratio striplines, and high paircount magnetically orthogonal twisted schemes such as cat5e multi's.

Parallel run conductors will use LC = 1034 EDC, the effective dielectric constant being about 4 to 6 for zips.

The prop delay argument is inaccurate when load and source impedances are very low in comparison to the line impedance.

To answer the question "why are we going in 300 or more directions?" That's easy. The misconceptions which abound confuse the issue.

jn
Almarg, an excellent post.

You are correct in interpretation of my 2005 statement, it is precisely what I said AND MEANT at that time.

HOWEVER, my statement then is correct ONLY with respect to lines which have an impedance which matches the load. At the time I made the statement, I had not adequately considered what the extreme mismatch between load, line, and source would do with respect to the settling time of the speaker wire. As it turns out, the only time the naked propagation delay is valid, is when the load matches the line impedance.

My concern is really only for midrange signals. It turns out that settling times for 10 foot zip cords which are terminated in 4 or 8 ohms midband, will be in excess of 5 uSec (Cyril Bateman actually measured this using a reflection bridge) and calculations bring that out in excess of 20 to 50 uSec. Given that humans demonstrate interaural discernment at the 2 uSec level give or take, this settling time falls within the possibility of audibility.

You skin question...I don't see any way to post graphs here, so I'll have to use text.

For a 1.5mm diameter wire at 20 Khz, the exponential solution states that at the center of the wire, there will be a current density which is 20% of the density at the surface.

Using the exact solution, the current density at the center of the wire will be 72% of the surface current density.

The exponential approximation is in error by a factor of 3.6 for a 1.5 mm dia wire at 20Khz.

I am not a cable manufacturer. While I have designed cables, they are always for my own use. I have in the past, provided to at least one (maybe two) cable manufactureres, the equations and understandings to allow them to create any cable of any impedance they wish, either for their own use or for their product line. All information was given freely with no restrictions. Under no circumstances have I profited either monetarily or via materials as payment for information. All materials I have ever used to construct cables, either for test or private use, were funded by myself.

In addition, the information given to that (or those) cable manufacturers is exactly what I have posted on multiple forums for all to use.

The most important thing any technical person can do is to continue learning. Should that learning provide new insights and understandings which conflict with prior knowledge, so be it. Nature of the beast. I am not immune to learning either.

jn
I have copied your post and am interjecting comments in "" "" marks, it gets less confusing that way. I wish I could color my inserts red, but such is life..

First however, one clarification on a comment you made earlier, that a vacuum dielectric would have no capacitance. Totally wrong. Capacitance is proportional to epsilon free space times epsilon relative. For a vacuum, epsilon relative is 1, and epsilon free space is 8.854 times 10e-12 farads/meter. I DO NOT UNDERSTAND HOW AN ENGINEER COULD MAKE THIS MISTAKE.

How are you calculating impedance at audio to such low levels?

""As I've stated prior, hf impedance is 1/sqr(L/C) At lower frequencies inductive reactance is very small, and the conductor resistivity starts raising the impedance. The full form is of the style "(R +L)/(C+G)". Unfortunately there is no equation editor on this site..sorry.""

The impedance rises rapidly at audio frequencies and is tremendously non linear. A cable can very easily be 600-ohms at 100 Hz, and drop to 50-ohms at 20 Khz with the open short method.

""I've stated that as well If you wish a general feel, the Belden website illustrates this for a general 75 ohm cable. For audio use, I recommend a value 2 to 6 times the hf value""

In don't see any liberties being taken to reduce an engineer's work load when it isn't even working as a transmission line. Oh it's "transmitting" all right, but not voltage.

""Do yourself a favor. Get an HP 8721A reflection bridge and look at the reflections which occur in the audio bandwidth. You will learn something new.""

As short as these cables are, open - short method is used to derive "impedance" even though there is no real impedance as the cable are far too short to manage such LONG audio wavelength. To be a factor, the cable length has to be at least 10X or more the quarter wave length of the frequency of interest. This relates to the fact that a voltage change has to happen BEFORE it gets to the end of the cable and audio speaker cables transit times are too fast for this to happen.

"" you are repeating generalizations and approximations which were simplified for engineering use. This discussion is beyond that. You need to ask more questions and make fewer incorrect generalizations.""

I'll jump to one other erroneous statement of yours for brevity. You've provided quite a bit of erroneous statements, but I believe everybody's time is better served by you asking questions on this topic. I am happy to teach you if you wish.""

The skin effect calculation is "wrong"? Well, All I see is you have a different opinion right now. Multiple credible sites use the most common methods and all arrive at about 18-mils at 20 KHz. Where is your documentation on your method? I agree that "approximations" can boil stuff down too far. Saying so is one thing, showing us is another. We're all tired of sayings.

Documentation?? On Bessels?? Really?

Do yourself a favor, google Bessel functions, google skin effect approximation, look it up in a good E/M textbook, something. I gave you an exact engineering statement on how time varying rate of change Lenz effect current exclusion occurs within a cylindrical conductor, and you come back with that???

You need better sites. Just because it's on the internet doesn't mean it is correct.

Please pay attention: The exponential equation is the solution for an E/M PLANAR WAVE driving into a conductive surface NORMAL to the boundary. It is NOT THE EQUATION FOR CURRENT REDISTRIBUTION IN A CYLINDRICAL CONDUCTOR WHERE THE CURRENT IS AXIAL. Skin effect in a cylindrical conductor is a consequence of Faraday's law of induction within the conductive material due to the internal magnetic field caused by the axial current. The exponential equation is an APPROXIMATION EQUATION used so that engineers do not have to get mired into the bessels. ""

I still see the yearning to be like the RF guys. Why?

""If this question is intended for me, you are barking up the wrong tree. What I speak of here is a very small subset of what I do for a living.""

I have thick skin so getting some good heads to knock me around is actually fun. Learning is NOT a spectator sport.

""It is good you have a thick skin, you are going to need it. You are not in Kansas anymore, Toto.. (no offense intended, I just HAD to use that statement..)""

I have been told you are an engineer. What I have seen posted by you is a mixed bag of engineering facts, incorrect statements, typical internet factoids. Are you an engineer, and if so, what kind?

Me, I am an electrical engineer. I design, build, and test superconducting magnets for particle accelerators, medical synchrotrons, antimatter confinement bottles, and MRI's....in addition to my other responsibilities which are more esoteric.

I appreciate and share your desire to maintain some semblence of scientific reasoning in all this. I just have a rather more advanced understanding of the problem, and find it is always necessary to teach others what they need to know. Your need to learn this is by no means unique in this regard. As I stated initially, "we" are going in 300 or more directions because so many people, you included, continue to promote somewhat erroneous engineering and physics concepts. Promotion of erroneous beliefs is part of the problem, not part of the solution.

jn
Rower,sorry to respond before you have a chance to see my last post..

These two paragraphs tell me everything I need to know about you.

"quote"
So let's say you arrive at your "complex" impedance by adding the vector sum of the real and imaginary (capacitance and inductance) parts. That would be HUGELY capacitive to get to an 8-ohms value with such low real component resistance and inductance. Most of the magnitude is a CAPACITOR! Why on earth would you want to load the circuit with all that capacitance when POWER or VOLTAGE is NOT dropped across imaginary values but only the resistive one? Capacitors and Inductors store voltage and current, only to release it later on (minus their internal resistance, anyway). Add a bunch of imaginary capacitive component to your speaker leads and you create a messy situation even at RF. Talk about phase shift and imaging issues, there is no transfer of energy, just storage and release of energy at in opportune times. It doesn't sit around forever. The higher the capacitance, the worse it gets. We aren't storing nuts for the winter, we want to eat them as the come down the line.

The skin effect calculation is "wrong"? Well, All I see is you have a different opinion right now. Multiple credible sites use the most common methods and all arrive at about 18-mils at 20 KHz. Where is your documentation on your method? I agree that "approximations" can boil stuff down too far. Saying so is one thing, showing us is another. We're all tired of sayings.

"end of quote"

It is quite clear that you have not taken any courses in E/M theory.

I would be happy to recommend some texts for you. Don't worry, I won't recommend Jackson nor Becker. Both are far too involved for you (actually, for all humans). I was thinking Rojansky or Shadowitz perhaps.

Or ask.

As a start, several equations along your path of learning.

E = 1/2 L I squared
E = 1/2 C V squared
Z =sqr(L/C)

Using these equations, you should be able to determine the relationship between the energy stored within the cable as a consequence of capacitance, and the energy stored within the cable as a consequence of inductance. You may even note that they are equal when the signal travelling down the wire has the voltage to current relationship which matches the characteristic impedance of the cable.

You may or may not understand that the only signal that can travel down a wire pair is a signal which has the voltage to current relationship consistent with the cable impedance. It does.

You may or may not realize that is is impossible for a cable to carry a signal at the base propagation velocity if that signal has a V to I ration which is not that of the cable.

Therefore, when an amp says "100 volts" into a cable which has a characteristic impedance of 100 ohms, that 1 amp signal will travel to the load at the line impedance. NOT THE LOAD IMPEDANCE. If the load impedance is 100 ohms, the event is over once the signal arrives, typically 2 nSec per foot.

If the load is 10, one transit will NOT produce 10 amps into the load. It will take quite a few.

Very important point... YOU ARE CLAIMING SUPERLUMINAL SIGNAL VELOCITIES.

Doesn't happen.

AND, what I am saying has been measured. Get a reflection bridge.

you said:

""Information is power...get some.""

pssst. I have news for you..

Be nice, get nice. Be arrogant, get same.

John
H Geoff, same employ for me, same games for you I see. It'd be a boring world if you conformed...I don't want a boring world..

Rower..I just knew I'd mess up the quotes...sigh...

Audiolab...

Much of what Rower has stated is in error or misconstrued, you should not expend energy confronting such content.

A general question:

Is it possible to bold or italicize in this forum? I'm trying to be clear and not mis-attribute.

jn
You cite audioholics as a source???

That explains a lot.

Gene D's a nice guy. Some of the articles are pretty straitforward, even though I don't care for the style. I didn't even mind that he quotes some of my technical explanations in some of his articles. On occasion he'll ask me to write a technical article or two for him, but we've not gotten together on that. What I prefer to write is a tad over his target audience with respect to E/M theory, and he would rather have the debunking style.

But to use his site to debunk of what I'm discussing is funny. The last person to do that was trying to teach me skin effect from AH, and he was quoting me in an attempt to teach me my quotes....incorrectly btw. Hmm, you appear to be the second one..

You never answered my question. Are you an engineer, or did you learn skin effect on the web? I asked that seriously, because you had no clue as to what I was speaking of with respect to skin effect and Bessels. You still do not know that the exponential equation is based on normal e/m waves at a conductive boundary, and it is inadequate for audio frequencies and audio size wires.

Rod Elliot's also a nice guy. But he's still not an E/M guru, nor does he have a good handle on EMC theory.

As I said, you need better resources. I mentioned a few, but you could just ask. Do you really believe that websites like that are sources for E/M theory??

As to your belief that cables cannot be transmission lines. Silly and inaccurate. Get a reflection bridge and see for yourself. Cyril Bateman did..

You have a lot to learn.

jn

Rower,

A simple followup.

Your first post to me included your words.."""information is power. get some.""

You are arrogant without foundation to be so.

I provided actual engineering on skin and cables, most taken directly from UNDERGRADUATE engineering E/M texts.

You "counter" with non peer reviewed content from audio hobbyist websites.

Your technical discussion attempts appear to be cut and pastes from online sources, mainly the same audio hobbyist websites, and how you meld them together tends to be both inconsistent and inaccurate, as though you do not have a real understanding of the topic..

Your attempt at diverting the discussion into one of ego has been seen before.

Like this gem...

Stated by rower::

But, I think some of this deservedly stuck to me with a little bouncing off me and sticking to you. True class keeps its class at all times. Yea, it's tough, I know. We do our best. Me, I'm fine with good information, being corrected and moving on. I don't use my knowledge to go hunting for those that don't without any real regards for the actual topic, just the hunt. Grow some civility with your posts and more will follow. You seem to be aware of this, so why not change it? Witness...

end of quote..

How old are you??? Bounce off me stick to you??? Stick to topic and please post more like an adult.
Enough of the unpleasantries, perhaps that chapter can be left behind? Your call.

1. Skin effect within a wire is NOT correctly calculated via the exponentional equation in the audio bandwidth. Skin effect is not as pronounced as the exponential equation describes. That is because the exponential equation assumes the energy is an E/M wave impinging on hte conductive material, NOT being generated by internal currents. You clearly have a problem understanding this. Do us all a favor, E-mail the owners of the sources you are quoting from , Rod Elliot the owner of sound.westhost, or Gene Delasalle, owner of Audioholics...give them verbatim everything I've stated on skin effect, ask them if I am correct. Both will either agree with what I've stated, or they will go to their trusted sources to ask what the story is. In which case, I might get some e-mails. I haven't been in contact with Rod in years, last time we discussed techniques for measuring doppler distortion in speakers, maybe 8 years ago... Gene, I discussed some article possibilities a few months ago.

2. Cables as t-lines at audio frequencies. Here, I guarantee both of your audio hobbyist website "sources" WILL have to contact higher level technical resources. There are only two sources on this planet I am aware of that understand this and have MEASURED, modelled, and quantified it cleanly. Cyril Bateman, and myself. (there may be more, I am not aware of them). Cyril wrote a really nice but unfortunatly extremely technical article which goes over the heads of most people. I am using this understanding to better a work project. Repeat, actual hardware.

I shudder at making this post so long, but the delays are incomprehensible to me...

Rower Quote/question:

I'd rather have half the knowledge and work towards a solution than all the knowledge and sit there with it. Jneutron, where are "our solutions" as you see them? What attributes do you look for?

End of quote.

Another slap upside the head. And you wonder why you have problems with someone of higher technical proficiency??

I stated that rather clearly before, go back and read. Human ITD discernment is 1.5 uSec interchannel max. Any effect which is in excess of that threshold cannot be discounted as inaudible. When the line/load mismatch is such that current group delay exceeds that threshold in the mid audio band where our undithered loclaization capability is strongest, method to reduce that delay are required.

Rower quote/question::

Jneutron, where should user's of Zobel networks calculate the impedance? What do you use when you suggest cable "impedance"?

End of quote..

I already stated that, you either missed it or did not understand it.

When a t-line is terminated by a load which matches the line, the amplifier DOES NOT SEE A CAPACITANCE. It sees a resistance. That is INDEPENDENT of the characteristic impedance of the cable. If you run a 5.77 ohm cable with 300 pf per foot and 10 nH per foot, into a 5.77 ohm load, the amplifier sees NO CAPACITANCE. NONE. You need to understand this.

When the load becomes higher impedance at higher frequencies, THEN the amplifier will see capacitance. It is a consequence of the line to load mismatch, NOT a consequence of the cable per foot capacitance in isolation.

When the load "unloads" at higher frequencies which are BELOW the amplifier's open loop unity gain bandwidth, the phase margin lowers and the system will be marginally or entirely unstable. A zobel is used to load the line at frequencies the speaker will unload at.

At audio frequencies, if you wish to know what the amplifier "sees" given the line impedance and the load impedance, just calculate the energy stored in the cable.

When line equals load, the inductive and capacitive energy storage will be equal, and it will be a minima. The amplifier will see a resistor.

When the line is much higher than the load, inductive energy storage will dominate.

When the line is much lower than the load, capacitive energy storage will dominate.

And, regardless of the ratio, all energy that is stored in the inductance and capacitance will make it to the load. I know full well where you get this dissipation schtick wit respect to capacitance and inductance, I've seen that site. AND IT"S WRONG. Both storage mechanisms introduce phase lag, not dissipation.

My post consists of technical theory and practice within the disciplines of E/M physics, amplifier design, and human localization. You would be better served asking questions on entities you either lack understanding of, or have a different opinion. Using audio hobbyist website content as technical argument material has it's limits.

Needless to say, you spouting t-line approximations which were taught for the RF guys is a waste of time. You do understand that it is taught that way so that we can use smith charts, right?

Geoff, you crack me up. btw, you never answered my question..how have you been? I hope all is well with you.

jn
Mapman,

Yah, they do look like the old style antenna wires...

That configuration will increase inductance and lower capacitance. Low C is always liked by the audio guys.

This also increases the characteristic impedance of the cables as well. Phono ins are 45K give or take, amp ins run 10k give or take. That style certainly is closer to the load impedance than normal coax (50-75) or twisted pairs (100-150).

There are a few ways to skin the cat so to speak.

Shielding as per coax protects the higher impedance inputs from stray E fields, that cable doesn't.

Twisted pairs is not as good for E field, but is better for magfield protection.

Parallel such as that is worst case for both in terms of shielding.

You've traded off noise and hum protection to gain in capacitance and impedance.

But honestly, if you have no noise or hum issues, that is great..Tain't broken, don't fix it.

All IC's can suffer loop induced hum and noise incursion from external magfields, but you seem very happy.

Is it a sound design approach? Yes, it certainly is. If you had noise or hum issues, it would not be the best design approach for your system.

ps. AS a general rule, if a circuit is lower than 377 ohms impedance, it is sensitive to inductance and time varying magnetic fields. If the circuit is over 377 ohms, it is more sensitive to capacitance and time varying electric fields.

It is also important to consider the level of the signals in the circuits as well. Speaker runs will be inductance sensitive to a point, but external magnetic fields can't really compete with 100 or 1000 watts of power.

jn
Geoff,

You mentioned tempered springs. Do you get involved in the tempering at all? I ask because antique clock mainsprings tend to lose their strength over time, and I suspect that I may be able to re-temper them after opening them up again, perhaps oil or maybe water quench. I was wondering if you've had any experience in that.

And, you did indeed blow off the question again. I wasn't asking about your work....I was asking about you.

John
Rower,
You said:

You seem to be a little too easy to get upset about some things so it's going to be hard to please you. I'll do my best.

My response:

Nothing could be further from the truth. Your statement is a diversionary tactic being used in an attempt to push blame on others rather than admit to your own arrogance. It is a common enough tactic, many people use it.

You said:

Zero capacitance? Sure, my perfect conductor example was just that.

My response:

NO, you stated that when the insulation is a vacuum, there is no capacitance.

Here, I'll refresh your memory...you said this exact thing on 3/15/2013:

4.0 The dielectric would be a vacuum so we have ZERO capacitance and velocity would be 100%.

My response to that was No, a vacuum dielectric does not have zero capacitance.

In addition, I provided the free space permittivity number, 8.854 times 10 to the MINUS 12 farads/meter.

You then stated :

That number is much higher than I would have expected, too.

My response...

Your kidding, right? I provide a physical constant, free space permittivity, and you say it's higher than you expected??? This physical constant is taught to ALL physicists and engineers, as well as in every AP physics course in high school I've become familiar with. It is needed to calculate capacitance. You've never seen it before, have you.

It is also "odd" that someone would thing that the number .000000000008854 is "larger than expected"..

This statement of yours is a very clear indication:

3.0 Carries energy in BOTH directions at the exact same time. Umm...this is a short circuit in reality.

My response:

WHAT???? A SHORT CIRCUIT????

YOU ARE ABSOLUTELY CLUELESS WHEN IT COMES TO TRANSMISSION LINE THEORY, FREE SPACE WAVE PROPAGATION, AND EVEN SIGNALS TRAVELLING THROUGH INDIVIDUAL CONDUCTORS.

Pay attention.

There are many websites out there which explain transmission lines and signal propagation. Find them and learn from them.

You stated:

I can't say I grasp speaker cable impedance at such low frequencies as they "rise" as the frequency drops, making consistent low impedances at audio seem implausible, at least to my way of thinking about the measurements. My guess is if you look at the cable like a T-line, the impedance is the same at any cable length. Of course, the low pass nature of the cable changes too.

My response:

I CAN say I grasp cable impedance. I can say I understand real skin effect. I can say I understand transmission line theory. The reason:

I am an EE. I do this for a living. I've done so for 35 years now. And I do it at a level which unfortunately, makes my resume incomprehensible to almost all EE's at the ScB level, most at the masters.

I am more than happy to share my understandings on the web so that others may learn.

I am not so happy when wannabe "engineers" attempt to use arrogance, belittlement, hobbyist website content, and rambling incoherent prose disguised as "technical speak" to badger others. Your type of "engineering" is one of the primary reasons cables and cable discussions are stuck in a quagmire.

I have provided valid reasons why cables can sound different, speakers, IC's, as well as power cords. Not that they all do, but rather, the physics processes which do impact the electrical function at some level.

That stated, if you wish to discuss actual technical things and how they can alter sound, fine. I've no problem with that. But you have to drop the shtick, it's old, it's worn, and you can't support the technical arguments.

jn
Geoff,

You've made me laugh now. I've only been considering heat tempering/quenching for antique clock springs, and am preparing to purchase firebrick to be able to cherry red springs about 6 inches dia un-sprung for oil/water quench. Believe it or not, I never considered LN2 post processing. Go figure.

I'll have to do more research on the spring materials, as I don't know if they have a martensitic finish temperature, or where it is, or carbon content either (most do rust). The application really frowns on microscopic cracking as that is a typical failure mode, but you've now got me thinking. Still, it's gonna take some research specific to re-working spring steel that's more than a hundred years old.

Personally for me, the funding stream is scary stuff. Luckily, the big project I'm working on is through 2016, and the smaller more esoteric ones go past 2020. But hey, the angst never goes away.

The vibration stuff I mentioned to you years ago went well, we used all kinds of piezo's, geophones, lasers, and some active tables for measurement and cancellation. It's amazing seeing voices cause measureable vibrations as seen on a scope on a 15 ton granite table.

jn
Mapman,

For impedance matching in speaker wires to make any difference at all, a few things need to happen.

First, the speaker impedance has to vary enough in the midband frequency range such that a mismatch can cause enough delay variation. If the impedance variation is not large, then playing with the speaker cables isn't going to matter much.

Second, the speakers need to be of sufficient quality that a clear and concise imaging effect occurs. Since the delays will really only affect imaging, if there is no imaging to speak of there will be nothing to "look" at.

Third, the program content has to be sufficiently rich in imaging content that central images are sufficiently stable that you are able to resolve any changes in off-axis image locations with respect to the stable central image. If the program content is insufficient for this, ya ain't gonna discern nuttin.

Fourth, if the program content images are derived by the normal pan pot back at the mixdown in the studio, then the IID parametrics are geared towards the studio monitors, not necessarily a good fit to any system in the field. Add that to a lack of ITD content, and then the user is hogtied into attempting to interpret images based on localization parametrics which have little to do with your system, setup, or your hearing capabilities.

Honestly, that's why I just listen to music for the talents of the musicians...

IC's are an entirely different ball of wax. IC's (especially single ended) and powercords conspire to create ground loops which compromise systems no end. It doesn't help that the engineering community has yet to establish test standards for equipment loop sensitivity, both as a victim and as an agressor. In general, the audio community pays little attention to EMC considerations. In the future, that will happen. But until that does, users can only swap IC's and PC's willy nilly to try to compensate for design flaws in components.

jn