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Actually, I did not..(long, with OMG, technical stuff inside.)

CJ: ""First off, what I did was an attempt of some qualitative analysis which may lead to why we hear the difference in cables due to their construction.""

No. Actually, what you did was cut and paste some info, that is all. You still did say you hear the diff, but have not yet answered that question.

CJ: ""I did already state clearly we don't even know what to measure let alone the effective instrumentation available to make such measurement valid to what we hear. Yet you still reiterate the forever tune of the naysayers: "YOU do not have the ability to measure it". So do YOU have the ability to measure it then????""
What is this naysayer crap you hide behind. Stick to the subject at hand.

You may be unable to understand what or how to measure, that is your limitation, not mine.


cj: ""Give me a break, please. I'm sick & tired to read this sterile commente all the time.""
I provided a correct analysis breakdown. You are bringing in this naysayer bullshit..please refrain from diversions, but instead, attempt to be correct in your posts regarding e/m theory.

CJ: ""Surely the signal propagation velocity is based on the ideal situation of vacuum or "free space", which would never happen in the realworld, regardless whatever construction of the transmission line, namely coaxial cable. So, your statement is WRONG.""
Surely?? You must attempt to find a text from which you can get the correct information. I used Jackson, Becker, Rojansky, and Shodowitz. (separate books and authors, If you wish the titles, chapters, pages, I can provide them.

The signal property in free space is exactly the equation I provided, and it is invariant on the form of e/m wave that is propogating. The velocity within a wire pair is also exactly as per the equation I detailed. That is invariant as well..

Didn't you learn this stuff in school?? Again, I could provide factual information in this regard.

Oh, btw..I really didn't understand the point you were trying to make in that last sentence..

CJ: ""For any straight ROUND copper conductors, the v.c. factor is the reciprocal of the square root of the effective dielectric constant (e) of the conductor insulation. Wherever there is insulation dielctric, there is a delay. This is nature. So how come your statement: "the ONLY transmission line which has the ability to transfer a siganl at the FREE SPACE velocity of the dielectric is a coaxial line"? You assume a coaxial cable is a bare wire w/o insulation?""

No. My statement says that if a coax is made with vacuum as the dielectric, the prop velocity of that coax will be the speed of light. My statement also says that if the dielectric is not vacuum, but instead a dielectric of value greater than 1, the prop velocity in that coax will be the same as the propagation of an e/m wave passing through that dielectric. For example, if you try to send a radio wave through a large volume of teflon, it will pass through it at the prop velocity consistent with teflon's dielectric constant. And that velocity will be identical to the velocity of a coax constructed of the same material.

Your statement is correct for coaxial constructions, that of reciprocal square root. Note that this is exactly what I said, with the equation v = c / sqr(epsilon mu), you are describing only a system with mu = 1, which is a constrained example.

CJ: ""The velocity of a wave in a coaxial cable can be expressed as a percentage of the velocity of light. For a coaxial cable using solid PE, it v.c. is 0.659, & e=2.26 ""

Of course. Why was it necessary to explain that? If you look at the equation I posted, you can clearly see the "c" in the numerator, with both epsilon and mu in the denominator, in that square root thing..

CJ: ""However, using foam PE where air is trapped inside the foamed dielectric, say RG-62 coaxial, the effective e is much less & v.c. is higher due to the air trapped inside, i.e. v.c.=0.80 & e=1.55.""

You explain that correctly, and again, this is consistent with the equation I posted.

CJ: ""I used v.c. & e to explain the delay of signal transmission which will surely give some perspectives easier for our readers to understand.""

This is a technical forum. Most already know this..

CJ: ""Now you bring in something else: "magnetic field" & "E field".YOU are now complicating the issue which I tried to explain in simple language.""

Your attempt to explain in simple language used material which had relevence only to propagation in free space, or within a coaxial construction. The simplistic explanation you gave, therefore, missed the majority of the boat, so to speak. In point of fact, the vast bulk of energy storage and propagation velocity modification is indeed as a result of the inductance of the system. Only for transmission line constructs which have a characteristic impedance close to that of the load, will the energy within the cable be minima, and of least impact on the end result.

If you cannot understand my explanation, just ask. It is not a sin, nor a sign of stupidity to ask questions. If it were an easy topic, it would be waaaay too boring.

CJ: ""So what "magnetic field" & "E field" are to do with what we hear? Please explain it in simple language so that our readers can understand.

The bunch of forumulae won't help anyway. You put them there to scare
off people?""

No. I put them there to explain to YOU that what you posted was only the simple relation for prop velocity in free space. You missed entirely, half of the physics. That being the magnetic field and the inductance.

Those equations WERE the simple explanation.

CJ: ""So let me go back to H & E field you bring forth which you failed to explain why you mentioned them relative to cable sonics.""
I mentioned them because of the inaccurate way in which you attributed free field propagation to constrained propagation.

CJ: ""The relative amplitudes of electric field (E) & mangetic field (H)
due to a signal passing through a transmission line, say, a coaxial cable is determined by the capacitance & inductance per unit length of the cable (assuming NO, repeat no reflections from the load).""
Yes. correct.

CJ: ""The characteristic impedance (Z) = E/H = square root of L/C.""
Again, correct. And, the characteristic impedance is the impedance where the amount of energy stored within the inductance is equal to the amount of energy stored within the capacitance. This relationship can be easily derived, and is the exact reason that the advancing wavefront will not reflect when it hits a matched load, as the load satisfies the parameters that have setup within the transmission line.

CJ: ""Another simple equation for Z is Z= 101,600/capacitance x v.e. of the insulation dielectric.""
Simple, yes..accurate..no. What is missing is the energy storage as a result of mu, which is the inductive relation. This simple equation was derived for a specific need, that of coaxial cables. It cannot be considered for use in any other cable construction, as that is an incorrect use of the equation.

CJ: ""From the 2nd formula, we can see the faster is the v.e of the insulation dieelctric, lower the the impedance.""

It is correct only for a coaxial system. It is useless for any other.

CJ: """You could be a great scholar, but you got make our readers understand what you want to tell.""

It is irrelevant whether or not I am a scholar. What is relevant is the use of the correct equations for the correct situation. You have pulled some very useful equations, and used them incorrectly.

CJ:""PS: the info. given my my posts are referenced from:
Radio Engineers Handbook, Pulse, Digital, & Switching Waveforms,
& Reference Data for Radio Engineers.""

That certainly explains why you used them incorrectly.

If you go back to that text, hopefully, you will find the constraints that should have been explained to the reader, so that they understand which situations are not covered by the formula you used. If you do not find that, perhaps you should e-mail the authors and explain to them the fact that they neglected to specify the boundary conditions and system constraints which apply to the use of those formulas. E-mail them these posts if you wish, so that they understand. Then, tell us what they said.

They are good formula, but they are not general ones which apply to non coaxial constructions, which the bulk of speaker wires are not.

Oh, almost forgot..relevance to what we hear..

Both capacitance and inductance within a speaker run are energy storage mechanisms. And, both are lagging.. Consider the response to a sine wave into a load in the first quadrant of operation. As the voltage rises (charging the capacitance of the cable) the current also rises (charging the inductive component). At the peak voltage and current, the energy storage within both components are at a maximum. Only when the cable z matches the load will this storage be at a minima.

This energy storage is not insignificant with respect to the levels of the energy that are being delivered to the load..they are in the 2 to 10% regime, depending on the z/load mismatch. They are orthogonal to the signal we are trying to listen to (90 degrees lagging for sine wave only) They cause group delay within the capability of human hearing..

This storage is easily calculated. Measurement of the group delay at typical speaker load impedances is way beyond the majority of engineers out there. They cannot design a load or cvr capable of the low inductance required for accuracy.

Cheers, John


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