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It took me a couple of viewings to wrap my head around what was being explained in this video. (Yes, I'm a knucklehead.)
I would like to hear a civilized conversation about what it explains, on this forum, especially by people much better versed in the subject than I am.
Follow Ups:
It shouldn't. None of this is new w.r.t. cable electricity or anything, and there is nothing in this video that has any impact on audio. Technically the position of Jupiter and the moon have an impact on electrical transmission in cables.
Having a theoretical impact and having an audible impact are not the same thing. Cable advocates love to talk about dielectric constant and dielectric absorption but have you seen even one of them quantify these parameters for a real cable and then calculate what impact that will have any an audio signal?
So why don't cable floggers (and cable companies do this?). 2 reasons. 1) Most of them don't possess any real significant knowledge of electronics or physics to accomplish this, heck, not even to an order of magnitude. 2) Their customers would not like the answer.
Bag of wind getting all worked up. You really must think you're the smartest person in the room all the time. No wonder people laugh at you behind you're back. If you're trying to convince everyone you don't know what you're talking about you're doing an excellent job.
I suspect the measurement of some of this gets pretty....dicey....as well.
For example? In microelectronic fabrication? We used a 4-point probe. 2 probes carry a fixed voltate, the other 2 are used to measure current. From this? Resistivity can be calculated. But you need to know a LOT about the system to get a good value....Voltage and probe Spacing, to start.
Too much is never enough
"When you control the Mail you control Information." - KramerLet's review the bidding. A simple battery hooked up to cables that demonstrate how fast it takes to light up a lightbulb is actually not an example of a signal. But in electronics like audio electronics there is a signal, a signal contains INFORMATION. Smoke signals contain information, Morse code system, ships use flags for signaling. So, whether the audio system is analog or digital the cables involved provide a means for the "electronic audio signal" to be transferred or transmitted from the source to the speakers. I'm not referring here to power cords which do not transfer information, thus no signal, according to this definition of signal. Power cords transfer "power" - but no signal.
The lightbulb experiment and similar experiments illustrate how electrons move, how current is achieved and perhaps how fast it takes for the lightbulb to light up. But those experiments do not help us understand how audio cables work because in audio cables we are transferring INFORMATION about the audio waveform, so speakers will be able to reproduce the acoustic waves that are faithful to the "electronic audio waveform."
The signal in audio cables is simply the alternating electrons - the alternating electrons alone provide the audio waveform, with two wires + and - required for the push-pull of the electrons in the conductor. Electrons vibrate back and forth at precisely the instantaneous frequency of the audio waveform. The motion of electrons produces moving charges, current and the alternating electric and magnetic fields AND the Poynting vector. But only electrons contain the information, so they are the signal.
The fields and Poynting vector are all part of the physics but they are not the signal. I'm not saying they aren't important but they aren't the signal. The free electrons should flow easily on one direction along the x axis for greatest efficiency, and purer metals and long crystal metals allow electrons to drift more easily along the x axis so there is less distortion and higher current can be achieved. The electron "drift velocity" is the average speed of electrons, taking into account the electrons that veer off course in other directions off the x axis.
Edits: 02/24/22 02/24/22 02/24/22
Some other AudioQuest innovations for cables and power cords include but are not limited to, highly polished surfaces of solid core and stranded conductors, control of direction for power cords, HDMI cables, use of LGC Long Grain Copper wire, high purity wire.
Edits: 02/13/22
...
Edits: 02/09/22
There is momentum in the electromagnetic field.
And when viewing the EM field in a moving frame, electric and magnetic fields mix & transform: that is literally the origin of Special Relativity.
Nt
Current doesn't flow through wires. Current is a calculated value and is a scalar quantity. It has no direction or speed. So, essentially current is not alternating in an AC circuit. Only the electrons are alternating direction.
Electrons don't "flow" in audio circuits. They wiggle back and forth at very slow speeds, about a meter per hour, and they wiggle back and forth according to the audio waveform so they move on average only about a millionth of an inch at a time. Net velocity of electrons is zero. So you really can't say they're flowing. Electrons are the charge carriers, the current is a function of the number of electrons in a cross section of the wire. When electrons travel on one of the two wires + and - they travel in the opposite direction on the other wire.
The energy that exists outside the wire is not the signal. The energy outside the wire is the electric and magnetic fields, I.e., Poynting vectors. The signal is the electrons. I say it's the electrons because that's what causes the speakers to emit sound ultimately. The electrons moving back and forth in the speaker voice coil on the + and minus wires produce an alternating magnetic field that interacts with the speaker permanent magnet to push and pull the speaker diaphragm back and forth according to the audio waveform transmitted by the amplifier.
Almost everything else is a red herring.
geoffkait said:
The energy that exists outside the wire is not the signal. The energy outside the wire is the electric and magnetic fields, I.e., Poynting vectors. The signal is the electrons. I say it's the electrons because that's what causes the speakers to emit sound ultimately. The electrons moving back and forth in the speaker voice coil on the + and minus wires produce an alternating magnetic field that interacts with the speaker permanent magnet to push and pull the speaker diaphragm back and forth according to the audio waveform transmitted by the amplifier.@geoffkait.
Wrong!
LOL, you still don't get it after all these years...
This is how it was explained on an Agon thread.Quote:
shadorne5,793 posts08-01-2017 1:22pm
@jea48
" The speaker transducer moves forward and backward according to EMF acting on the voice coil - see Faraday's law and Maxwells equations - so both +ve and -ve current direction along the speaker wire causes transducer movement.
A wire with directional properties would be a disaster for reproducing accurate audio. So Audioquest marketing mumbo jumbo is obviously just mumbo jumbo - Otherwise their products would not work. "
///////////////
hermam responds:herman2,143 posts
08-06-2017 12:42pm
" about this "" The speaker transducer moves forward and backward according to EMF acting on the voice coil - see Faraday's law and Maxwells equations - so both +ve and -ve current direction along the speaker wire causes transducer movement. "
Herman's response:
" Again, it has nothing to do with we commonly call "current" which most visualize as electrons flowing back and forth. It simply doesn't work that way. There is an electro-magnetic wave that transfers energy to the coil of the speaker. If applied to a resistor it creates heat. If applied to an inductor (coil) it creates a constantly changing magnetic field which pushes and pulls against a fixed magnet creating motion. Those stuck in a world of flowing electrons are just that, stuck there. Energy flows, electrons do not. "
/ / / / / / / /
What is Electronics
Ralph Morrison●May 3, 2018Storing or moving energy.
There is a common misconception that signals are carried in conductors. Somehow this association crosses over to the idea that conductors carry both signals and energy. A few simple calculations can show that this is a false idea. Consider a 50-ohm transmission line carrying a 5-volt logic signal. The initial current at switch closure is 500 mA. A typical trace is a a gram-mole of copper that has 6 x 1023 copper atoms (Avogadro's number). Each atom can contribute one electron to current flow. Knowing the charge on an electron makes it easy to show that the average electron velocity for 500 mA is a few centimeters per second. What is even more interesting is that only a trillion electrons are involved in this current flow. This means that only one electron in a trillion carries the current. This also says that the magnetic field that moves energy is not located in the conductors. The only explanation that makes sense is that energy in the magnetic field must be located in the space between two conductors. Conductors end up directing energy flow - not carrying the energy.
The electric field in the conductor that causes current flow presents a similar picture. For a transmission line trace 5 mils above a ground plane, the electric field strength in the space under the trace is about 49,000 V/m. The electric field inside the conductor might be 0.1 V per meter. Energy in an electric field is proportional to field strength squared. The ratio of the square of field strengths in and near a conductor is about 2.4 x 1011. It is safe to say that there is very little electric or magnetic field energy in a trace or conducting plane. Since the energy is present and it is not in the conductors it must be in the space between the conductors. This is true for sine waves or square waves at all frequencies including dc. This one idea is not often discussed in circuit theory. This one idea solves most interference problems. This one idea is at the heart of a good circuit board layout. If the energy that represents information is carried in spaces it makes sense that we must keep these spaces free from interfering fields. The path should also control the characteristic impedance so there are controlled reflections. What we really need to do is supply a smooth path for logic energy flow.
Best regards,
Jim
Edits: 02/20/22 02/20/22
You always put too much faith in their concept of reality. It's kinda funny, you can't explain it yourself. Why are you always quoting Herman? We have already established the facts in this case, including how the Poynting vector is created and where the electric field and magnetic field and Poynting vector are located, and what produces current. There is no more mystery. Besides, what you quoted looks an awful lot like gobbledegook.
Edits: 02/20/22 02/20/22
Fact is the signal does not travel in the conductor, as you continue to say to this day. If it did what is the carrier? Not the electric charge... So if the signal travels in the conductor explain your theory. And don't say the EM wave travels in the conductor, and that carries the signal. The EM wave does not travel in the conductor. Energy does not travel in the conductor.
The signal energy travels in one direction from the source to the load in the form an an EM wave at near the speed of light in a vacuum. The signal travels in the spaces between the conductors. The load consumes the energy. The load does not consume the electric charge. If you had taken the time to read the Ralph Morrison Link Morrison explains it quite well how it works. He explains why you are wrong... gobbledegook? Hardly...
https://www.electronics-related.com/showarticle/1165.php
How many times were you told on Agon the signal does not travel in the conductor? By well respected educated EEs I might add. For one the Late Almarg. You put down herman but he taught this stuff at the associate degree level.
Best regards,
Jim
It's the ENERGY that travels outside the conductor. But the energy and signal are not the same thing. The signal travels inside the conductor, that's why the metal and purity of the metal affects the sound. The Poynting vector travels in the direction of electron motion, so it reverses direction along with electrons. The Poynting vector travels through the dielectric material along x axis. The Poynting vector is the cross product of the electric and magnetic fields, which are both perpendicular to the Poynting vector and to each other, in the y and z axes. The electric and magnetic fields alternate one after the other along the x axis. The Poynting vector is pointed in the instantaneous direction of electron flow, so the Poynting vector also alternates direction. See video at the top of this thread regarding physics of the Poynting vector.
Edits: 02/21/22
Then how does the signal traveling in the conductor pass through the windings of an output transformer?
Could you get any further off the subject?
It's not off subject at all. My question blows a hole in your theory the signal travels in the conductor doesn't it. As usual your response is to deflect, avoid, answering the the question.
" There is a common misconception that signals are carried in conductors. Somehow this association crosses over to the idea that conductors carry both signals and energy. "
There it is.... End of conversation...
It depends on what you think the energy is and what you think the signal is. I've been trying to get a straight answer out of you on this for years. Your response is always to quote your hero. You did it again. But no one ever said the signal is carried outside the conductor. Only the energy or energy flux.What we know is the Poynting vector travels outside the conductor but the Poynting vector is not the signal. The units of Poynting vector are Watts per meter squared. It's the energy flux. Hel-loo! Does that look like a signal to you? Really? Is the signal the electric field? The magnetic field? They are outside the conductor too. What is the signal? That's what I'm asking you.
Edits: 02/22/22 02/22/22
The signal is the EM wave. The signal EM wave transfers the energy from the source to the load at near the speed of light, in a vacuum. Though the speed of the EM wave signal is limited by the dielectric insulating material used covering the bare conductor. Do you suppose that might explain why the type of insulation used to cover the bare conductor can have an effect on the sound of ICs and speaker cables?
The signal does flow in a conductor at near the speed of light. The signal energy does not flow in the conductor at near the speed of light.
The signal EM wave travels through the dielectric space between the conductors.
You have yet to explain how the signal travels in the conductor at near the speed of light. It doesn't... The AC signal in the conductor vibrates and hardly moves at all in the wire. You know that...
For most audio cables there is one conductor per side, + and -. The electrons move in one direction on one conductor while simultaneously moving in the opposite direction on the other wire. Electrons switch direction according to the alternation rate of the audio waveform. It's the alternation of electron flow that ultimately produces sound in speakers, that moves the diaphragm back and forth.Even though electrons move very slowly they change directions very rapidly, according to the instantaneous audio waveform, 20-20k Hz. That's why I said somewhere recently electrons travel only about a millionth of an inch at a time. In any case, this is the core of the audio signal in cables, the alternating electron motion on both + and - conductors, which in turn creates moving charges, I.e., current.
The audio waveform of course originates at the source and is amplified along the way. The electrons do a little dance, the wiggle wiggle dance, to the tune of the audio waveform.
Alternating current and alternating voltage produce the magnetic fields and the electric fields, . The Poynting vector is simply the cross product of those two fields. The Poynting vector also alternates direction along with the audio waveform. You can forget about speed of light. That is only a red herring. In fact, this discussion is really about low speed physics, not high speed physics since electrons move only about a meter per hour.
Edits: 02/23/22 02/23/22 02/23/22
You are flat out wrong...Click on the Link provided below.
Download full-text PDF
Understanding Electricity and Circuits:
What the Text Books Don't Tell YouIan M. Sefton
School of Physics, The University of SydneyYou will have to copy and paste the link.
https://www.researchgate.net/publication/255626544_Understanding_Electricity_and_Circuits_What_the_Text_Books_Don't_Tell_You
Edits: 02/23/22 02/23/22 02/23/22 02/23/22
This guy agrees with me. Thanks for sharing! Eventually you'll find someone who agrees with you, like the monkey at a typewriter writing the plays of Shakespeare. Does your new hero talk about audio cables or the audio signal at all in his paper? I assume your answer is no. I suspect you should probably at this point figure out what I mean by the "audio signal" in cables or what is meant by the word "signal" in audio cables before proceeding any further. And figure out the difference between signal and Poynting vector. Otherwise this is going to be a goat rope. I have some trained deprogrammers standing by.
Edits: 02/23/22
"The electrons moving back and forth in the speaker voice coil on the + and minus wires produce an alternating magnetic field that interacts with the speaker permanent magnet"That isn't completely explanatory either in my opinion.
There is a direct force on the moving electron in a combined EM field:
F = q(E + v x B)
making a force perpendicular to the net current flow and the external magnetic field. The "E" is the electric field producing the primary current flow axially down the wire (the consequent 'v' of electrons), but then the v x B term comes into play (assuming the B is large and externally generated as a voice coil in a permanent magnet).
In a physical wire with a conduction band (which has low resistance for some electrons) these electrons are then pushed to one boundary of the wire on the side.
At this point the electrons are somewhat bunched up but the nuclei and bound electrons, net positively charged, are displaced from the electrons by a slight amount. Now the electrostatic attraction pulls them together, moving the physical bulk of the wire (whose mass is dominated in the stationary nuclei in the crystal). This is then experienced as a physical force in the wire in the v X B direction. This is the speaker.
The magnetic field produced by the motion of the conduction electrons itself is a secondary effect, which produces a force back onto the permanent magnets to satisfy Newton's 3rd law. But it's not necessary to explain the force on the wire that is the purpose of the speaker.
Edits: 02/11/22 02/11/22 02/11/22
I don't like the description of current flowing down the wire, if I can be so bold. Current doesn't flow down the wire. Current is a scalar quantity, a calculated quantity. That's why I think it's easier, and more correct to talk about electron motion. Current is one of the few things that isn't a vector, since E, H and Poynting vectors are all vectors.The rate of alternation of electron motion in audio (read AC) cables corresponds to the instantaneous audio frequency. It's the "push-pull" of electrons on two wires + and - that is the "audio signal," as it were. That's why I said electrons only move around one millionth of a meter at a time, then reverse direction. So, actually electrons don't really flow. And their net velocity is zero.
The electron drift velocity is the average velocity along x axis and takes into account all free electron "side trips" so to speak. E and H fields alternate and are orthogonal to each other and to the direction of electron motion at that instant in time. That's also the direction of the Poynting vector at that instant in time.
Edits: 02/11/22 02/11/22 02/11/22
well, in most physics cases, they use current density, which is a vector valued field. That's the source term in Maxwell's equations.
In practice, since that is assuming a fluidic classical current density which isn't actually true, it really means an integration over atomic scales such that there are a large number of electrons included and only the bulk average motion considered (thermal motion ignored), but small enough a volume/length scale such that it is still small compared to the macroscopic length scales of the wires.
This sort of approximation is very common and is equivalent to the approximations that let one go from kinetic theory of individual particles to Navier Stokes equations of fluid mechanics. That was a few of weeks of lectures in statistical mechanics and I've forgotten all the details but the end point was NS equations with classical heat diffusion equation derived.
Irrelevant information. Sounds very technical and you get an A for name dropping.
Explained in a much clearer way by Dave Jones. This is basic stuff.
https://www.youtube.com/watch?v=VQsoG45Y_00&t=2208s
Dave.
Nt
This is what you're supposed to learn in college electromagnetism, i.e. Faraday, Maxwell, Heaviside and Einstein.
Name dropper.
Knowledge is often defined as what's left after you forgot almost everything they taught you in school.
Light is not only responsive to gravitation, but it a source of gravitation through the stress-energy tensor despite having no mass.
But in practice its effect is completely minuscule.
Speaking of light, light is the signal in audio cables. How about them apples?Yes, everyone knows that spacetime warping bends light. But it's not gravitation on the classical sense. Obviously relativistic effects are not noticeable in everyday life. Nor are quantum effects, unless you look very carefully.
It's becoming harder to draw the line between classical physics and quantum mechanics and relativity. But getting back to the original discussion...-
Edits: 02/12/22 02/12/22
mrod,
Most of what he talks about is correct:
the electrical signals do not actually get carried inside the conductors, but rather, are represented by the electrical AND magnetic fields that are present for the most part OUTSIDE the wires.
I have been aware of this all my time as an Engineer, even though it was not specifically taught as such in school.
It can be helpful to think of the conductors as a set of "guide rails" for the EM fields, rather than the classic but misguided plumbing pipes concept.
He is wrong about the turn on of the light bulb, as EM fields do not propagate faster than the speed of light, and thus, the light bulb would not turn on for about 1 second after the switch was closed.
This would, of course, require a "perfect" set of conductors, with no inductance, no capacitance, and no resistance. He only mentions resistance, but implies the perfection of the other two parameters.
Real world wires (actually wire pairs), have all three, and due to the fact that most of the insulators are not a perfect dielectric, the velocity of propagation will be less than the speed of light, say somewhere between about 60% and 85% depending on the quality of the insulator dielectric.
I will cover some of the other aspects that this leads to with regard to audio cables, and why it does make a difference that the signal is not actually carried inside the wires, but for the most part, outside.
Jon Risch
The Electric field is orthogonal to the direction of free electron motion, the Magnetic field is also orthogonal to the direction of electron motion, x axis as well as to the direction of the E field. The Poynting vector, the cross product of the E and H fields, is in the same direction as electron motion.The Magnetic field is actually our old friend the induced Magnetic field that results from a moving charge in the wire, I.e., current. The E field is induced by voltage.I doubt anyone said fields propagate faster than the speed of light. In any case, more to the point, the E and H fields don't propagate along the same axis as the electron motion. But S the Poynting vector does.
An electromagnetic wave travels at light speed in a vacuum, of course, but in a medium it travels somewhat slower, in cable the speed is around 7/10 the speed of light, I'm referring to the Poynting vector here so that speed is through the dielectric material since the Poynting vector is outside the metal conductor. And all know what particle travels at the speed of light in a vacuum and somewhat less than the speed of light in a medium, right?
It should be noted that the strength of the H and E fields determines S the Poynting vector. And voltage and current determine the H and E fields. Current is of course calculated from the number of free electrons moving along the conductor per unit time. So I think one can safely conclude that the final result S, the Poynting vector, is a strong function of how freely the electrons can move in the metal conductor along the x axis.
Edits: 02/08/22 02/08/22 02/09/22
wires are necessary to support the boundary conditions that allows a magnetic field to be generated that will support long distance energy transfer efficiently at low frequencies, including zero frequency.
Otherwise, in free space the only possible energy transfer is electromagnetic radiation, and the coupling of that to physical devices grows more efficient at higher frequencies.
Actually, wires aren't necessary for audio. My system for example doesn't have speaker cables, power cords, interconnects, digital cable or much wire at all. I don't have fuses, large capacitors, large transformers, or even speakers. Yet I have very good sound. Think outside the nutshell!Audiophile axiom: You can't have an industry based on selling nothing.
Edits: 02/12/22
FASCINATING; Learned a lot..This dumb but is there an application for audio?
Thanks!
What is the "audio signal in cables? If you don't know what the audio signal is how do you know which metal conductor to use, how thick the conductor should be, whether to cryo the cable, if cables are directional, whether cables are sensitive to vibration, or sensitive to electric static fields, the importance of the dielectric material.So is the "audio signal" in cables one of these?
1. It's embedded in the electromagnetic field and travels at lightspeed
2. Energy - The Poynting vector
3. The Magnetic field
4. The Electric field
5. Alternating current
6. Electrons
7. Photons
8. The acoustic waveform
Edits: 02/13/22 02/13/22
All fine and dandy. But the professor, and the second group of scientist are more correct in their conclusions than he is.
Electrons flow at the surface of the wire creating the fields which they speak of.
Most electrons travel below the surface of the wire, at least for audio frequencies. That's why cryogenically treating the wire and direction of the wire affect the sound. Obviously for very thin wire you could say all electrons travel "near the surface."
Not sure about "civilized", but there were some conversations regarding that video here on AA. Can't find it with a search though. I think unless a YouTube video topic is actually listed in the subject or body of a post, it won't come up. Too bad because sometimes a post just starts with "this is interesting" and then a link. But I'm getting off topic.
As for the video, I recall enjoying and was quite intrigued by it.
Jonesy
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