This is an important word, a model. Some seem to live in models and not in a real world. It is quite easy to measure a real delay of a signal on the link or speaker cable and one will usually measure a value of some 5ns/m. I would like to see ANY measurement that would indicate that 100Hz wave propagates along a cable in a different speed than e.g. 10kHz wave and that such fictional difference is of any importance.
I would like to see ANY measurement that would indicate that 100Hz wave propagates along a cable in a different speed than e.g. 10kHz wave and that such fictional difference is of any importance.
Careful PMA diispersion is easily observed on any lossy line. That's not what we are looking at here, at 3000mi of cable it's different.
I am not speaking about overseas cables and necessary inductive compensation. I thought we were in audio and length in meters. Still, we can read similar reasonings for 2m of cable.
Sigh! A piece of wire is a classical object, even if the internal properties need quantum physics to fully describe and calculate. Dragging in 'quantum' to audio is what snake-oil merchants do. As a physics graduate you should know better, John. The key concept is 'model using the appropriate level of abstraction'.john curl said:With all that has been brought up showing the complexity of transmission line equations, it must be remembered that it is still only a MODEL, most of which was derived even before they discovered electrons, much less, quantum mechanics.
More advanced textbooks add the quantum mechanical aspects to current flow, and this further complicates the situation and infers the subtle nuances that our ears seem to detect in differences between connecting wires, due to geometry, or material properties of both the insulator or the conductor.
The difference in speed is not fictional. At audio frequencies cables are dispersive. However, this is irrelevant unless you are wiring a trunk telephone system. Then you just add inductors and accept reduced bandwidth instead.PMA said:I would like to see ANY measurement that would indicate that 100Hz wave propagates along a cable in a different speed than e.g. 10kHz wave and that such fictional difference is of any importance.
At very low frequencies it could be argued that cable propagation changes from waves to 1-D diffusion. That will set the trolls' pulses racing!!
From part 3...
The two ends swap geometrically decreasing reflections that, with a little smoothing, look just like an RC-charging curve.
🙄
2nd Volume, Chapters VI and VII of Heaviside’s Electromagnetic Theory describe all these phenomena in detail (and with a clarity that I haven’t seen in modern EM books). This, before he formulated the equation for a “distortion-less line” (in freq and in time domain).
http://archive.org/download/electromagnetict01heavrich/electromagnetict01heavrich.pdf
http://archive.org/download/electromagnetict02heavrich/electromagnetict02heavrich.pdf
http://archive.org/download/electromagnetict03heavuoft/electromagnetict03heavuoft.pdf
George
However, this is irrelevant unless you are wiring a trunk telephone system.
That's it. We are not at the telephone forum here and we are not working with kilometres of cables in high end audio.
The difference between so-so, and exceptional sound has nothing to do with fiddling with cable in these areas - I can go from one side to the other without even breathing on the things, the last time I bought "special" cable was 30 years ago ...
At very low frequencies it could be argued that cable propagation changes from waves to 1-D diffusion. That will set the trolls' pulses racing!!
The infinite R1/R2 ladder is a great interview question, just ask the person to do it by inspection. BTW for R1 = R2 it's the golden mean times R, must be something profound there.
With all that has been brought up showing the complexity of transmission line equations, it must be remembered that it is still only a MODEL, most of which was derived even before they discovered electrons, much less, quantum mechanics.
More advanced textbooks add the quantum mechanical aspects to current flow, and this further complicates the situation and infers the subtle nuances that our ears seem to detect in differences between connecting wires, due to geometry, or material properties of both the insulator or the conductor.
Please show some honest testing and proof to back up this silly claim about "quantum" anything making the sound different. You can't, it's just conjecture and silly subjective opinions mostly taken advantage of by those wishing to sell dumb audio products that only lighten the wallets of the gullible. Zapping audio cables with tesla coils does not make them quantum anything. It's just marketing BS...........period.

Did you brought them with you from the trip thru quantum mirror? 😀What about quantum fets, i have ...![]()
Quantum Mirror - Stargate Wiki
You don't have to bring in Quantum Mechanics to make a reasonably successful audio playback system, but it does help, if you are open minded enough to try to use it.
For the moment, I think that it would be better to avoid that 'controversy' here, but do note that mere linear equations does not REALITY MAKE, either.
I have found that wires and cables make a difference, and I, as well as Dr. Vandenhul (much earlier) and perhaps many others have found differences that deviate from the linear predictions. But I will not dwell on it here, because this is primarily an electronics thread and wire is only a small part of 'getting it right'.
To reiterate: There are 3 major areas to address when making an audio design: topology, layout, and parts quality. Each is essentially as important as the others.
Some secondary considerations might be elegant simplicity (don't just pile a bunch of parts in SERIES), internal distortion cancellation, and true freedom from generating FM types of distortion. This is where the subtlety comes in, and what 'wins' the listening contests.
Of course, you have to experience differences in audio components to actually make it all worthwhile. If you insist on double blind tests only, you will probably not get far, because you will not have any subjective feedback to guide you. Therefore what you get in the end, may measure well, but sound just OK. That is why hi end designer listen to their designs, subjectively.
For the moment, I think that it would be better to avoid that 'controversy' here, but do note that mere linear equations does not REALITY MAKE, either.
I have found that wires and cables make a difference, and I, as well as Dr. Vandenhul (much earlier) and perhaps many others have found differences that deviate from the linear predictions. But I will not dwell on it here, because this is primarily an electronics thread and wire is only a small part of 'getting it right'.
To reiterate: There are 3 major areas to address when making an audio design: topology, layout, and parts quality. Each is essentially as important as the others.
Some secondary considerations might be elegant simplicity (don't just pile a bunch of parts in SERIES), internal distortion cancellation, and true freedom from generating FM types of distortion. This is where the subtlety comes in, and what 'wins' the listening contests.
Of course, you have to experience differences in audio components to actually make it all worthwhile. If you insist on double blind tests only, you will probably not get far, because you will not have any subjective feedback to guide you. Therefore what you get in the end, may measure well, but sound just OK. That is why hi end designer listen to their designs, subjectively.
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If you insist on double blind tests only, you will probably not get far, because you will not have any subjective feedback to guide you. Therefore what you get in the end, may measure well, but sound just OK. That is why hi end designer listen to their designs, subjectively.
Since DBTs are done by ear, this is clearly nonsense.
Some of us rely on our ears. You rely on peeking. That's OK, it's what you need to do to sell to your niche customers who likewise trust their eyes and preconceptions more than their ears.
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