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Quote.
ELECTRIC CURRENT IS A FLOW OF ENERGY? Wrong.
Electric current is not a flow of energy; it's a flow of charge. Charge and energy are two very different things. To separate them in your mind, see this list of differences.An electric current is a flowing motion of charged particles, and the particles do not carry energy along with them as they move. A current is defined as a flow of charge by I=Q/T; amperes are coulombs of charge flowing per unit time. The term "Electric Current" means the same thing as "charge flow." Electric current is a very slow flow of charges, while energy flows fast. Also, during AC alternating current the charges move slightly back and forth while the energy moves rapidly forward.
Electric energy is quite different than charge. The energy traveling across an electric current is made up of waves in electromagnetic fields and it moves VERY rapidly. Electric energy moves at a completely different speed than electric current, and obviously they are two different things flowing in wires at the same time. Unless we realize that two different things are flowing, we won't understand how circuits work. Indeed, if we believe in a single flowing "electricity," we will have little grasp of basic electrical science.
In an electric circuit, the path of the electric charges is circular, while the path of the energy is not. A battery can send electric energy to a light bulb, and the bulb changes electrical energy into light. The energy does not flow back to the battery again. At the same time, the electric current is different; it is a very slow circular flow, and the electric charges flow through the light bulb filament and all of them flow back out again. They return to the battery.
Electric energy can even flow in a direction opposite to that of the electric current. In a single wire, electric energy can move continuously forward while the direction of the electric current is slowly backwards. In AC circuits the energy flows continuously forward while the charges are alternating back and forth at high frequency. The charges wiggle, while the energy flows forward; electric current is not energy flow.
http://amasci.com/miscon/eleca.html#cflowhttp://amasci.com/miscon/whatis.html
>>>>>>
Quote.
The speed at which energy or signals travel down a cable is actually the speed of the electromagnetic wave, not the movement of electrons. Electromagnetic wave propagation is fast and depends on the dielectric constant of the material. In a vacuum the wave travels at the speed of light and almost that fast in air.
http://en.wikipedia.org/wiki/Speed_of_electricity>>>>>>>>>
Up until 2010 I thought I had a pretty good understanding of electricity.
And then I read a thread on Audiogon asking about cable directionality.
Things have not been the same since.
I would really appreciate the views of those with degrees in Physics and or an EE degree.The Audiogon thread.
http://forum.audiogon.com/cgi-bin/fr.pl?fcabl&1274104190&openusid&zzMy first reaction to Herman's posts was what planet is this guy from.
I searched Google for other Physics links to prove Herman wrong. All I found was more of the same....>>>>
Here is a thread I posted on recently on Audio Circle.
http://www.audiocircle.com/index.php?topic=122264.0Jim
Edits: 02/21/14 02/21/14Follow Ups:
How important is wire directionality for each of the following?1. Capacitors
2. Resistors
3. Inductors, including tiny coil in moving coil cartridge
4. Internal wiring of amps, CD players, etc.
5. Wiring in crossovers,
6. Power cords
7. Transformers
8. Headphone cable
Edits: 02/28/14 02/28/14
How important is wire directionality for each of the following?
1. Capacitors2. Resistors
3. Inductors, including tiny coil in moving coil cartridge
4. Internal wiring of amps, CD players, etc.
5. Wiring in crossovers,
6. Power cords
7. Transformers
8. Headphone cable
As for #1 & #4 I asked Charles Hansen that question. His reply,
RE: Ping, Charles Hansen
Posted by Charles Hansen (M) on January 16, 2010 at 17:26:35
In Reply to: Ping, Charles Hansen posted by jea48 on January 16, 2010 at 15:32:09:
Every time that I have decided a priori that something can't *possibly* have any effect, I have always been proven wrong by listening tests at a later date. So I end up deliberately not listening to some things because I'm not sure if I want to know the answer...I have never listened for wire directionality. I have talked with enough people I trust to believe that it is real. Some of them think that it is part of the wire itself and is created as the wire is drawn to smaller gauges through the dies. Others think that it acquires its directionality by being played in the system.
I don't really know. I'm not sure that I want to know. We don't really want to get into some strange position of trying to make products that aren't really manufacturable or would end up costing twice as much to make as they do now.
~~~~~~~~~~
Please note that this is a completely different topic than RCA interconnect cables that are directional due to the way they are manufactured. In the old days everyone just used coax and one end was the same as the other. Now most companies use a twin-ax conductor that is the same that they use for a balanced XLR cable. Then there are *two* grounds. One is the shield and one is the internal ground wire right next to the hot wire.
Typically the internal ground wire is connected at both ends, but the shield is only connected at one end. Reversing the direction of these cables will determine to which component the shield is connected and will certainly make an audible (and possibly measurable) difference.
~~~~~~~~~
Finally, it should be noted that we *do* orient all of our axial-leaded plastic film capacitors. When the capacitor is wound, one of the leads will be connected to the outside conductor and the other lead will be connected to the inside conductor. Orienting the capacitor in the circuit properly makes a difference in the sound quality.
It took us a while to figure out how, but we built a machine that allows us to tell which end of the capacitor is which. It is a pain, but we sort every single capacitor and mark it for the correct orientation at each point in the circuit. If we had to *listen* to every capacitor to determine the correct polarity, I don't think anybody could afford to buy our products...
http://www.audioasylum.com/audio/general/messages/55/558658.html> > > > > > > > > >
As for #5 one would think so. Maybe the big boys do but keep it a trade secret..... I have no idea.
This guy doesn't.
Re: stranded or solid core power cord ?? need advice
« Reply #133 on: 6 Dec 2013, 06:24 pm »
http://www.audiocircle.com/index.php?topic=121391.120AJinFLA
Industry ParticipantSoundfield Audio Loudspeakers
Oh there's already a filter. It's in your power supply.
Well...not necessarily. In my equipment and maybe yours too. Things like power supplies would have been competently engineered (among other things, like line input/output impedance, etc, etc.) and thus largely immune to line cords and ICs, etc, etc.
But that (along with the price, production volume and brand/faceplate, etc) is what makes them "Mid Fi".
They lack "magical" properties when things like cables start getting swapped around.
In a "high end" component, the complete opposite may be true. The level of incompetence in engineering can be startling...but this is desired!! Thus, when a power or IC cable, etc. makes a dramatic difference, the street cred of the component skyrockets, it is "revealing" of a, b, c and d!!
So yes, while audiophile perceptions can be in error in the really real world (not theirs), it is impossible separate that from the fact that the cord (etc) could indeed be affecting the soundfield (pardon the pun) to audibility thresholds. Can't prove a negative, so take with a grain of salt that it could be real...or imagined.
Now with regards to "directionality", same applies. Remember, that cable is to be inserted into components on both ends. Are they "audiophile injuneered"? Also remember, that while the wire itself can't be "directional", the terminations can be different (including shielding as pointed out earlier). The impedance mismatch at either end load can differ. Reflections, settling time, etc. will be different
Whether that rises to audibility thresholds, or is just part of the imaginary effects, who knows? One would have to control test every individual situation...an obvious impossibility.
The capacitor thing is largely nonsense, that one would practically demand a controlled test to add yet another null to the heap.Oh and to the OP, forget stranded vs solid, that shouldn't enter the buying choice except for purely psychological reasons. Which may be all that really matters!!
cheers,
AJ
Start of thread, http://www.audiocircle.com/index.php?topic=121391.0
> > > > > > > > > > > > >#8) If stranded wire is used, just guessing the answer is no.
Edits: 02/28/14
Actually stranded wire does have a directionality because of the mechanical nature of drawing the finished gauges. The finished faw wire is wound on large spools and then the spools are combined pn another machine in order to weave or wind the finished construction I do not know of any company which can draw multiple strands and simultaneously wind a stranded configuration which sometimes can number hundreds of individual strands.
Stranded wire, if strands are individually uninsulated, may cloud certain aspects of directionality, as signal can "bleed" across the uninsulated strands and create a certain amount of smear. :itz wire avoids this, but then other factors like capacitance has a tendency to increase and this too may cloud the issue of directionality.
In the case of examining one particular factor, remember there may be many other mitigating, related aspects.
Just what exactly do you want our thoughts on? My hunch is that there is just some semantic confusion going on.
Think about an electric circuit compared to a V-belt and pulleys, they are pretty good analogies. They both just provide a conduit to allow the transfer of energy spatially from where it's available to the point where you want to do work. (work as in getting hot.)
If you don't do any work at the receiving end then all that happens is that some energy is wasted by the less than perfect transfer mechanism and also some is stored in the mechanism itself in the process of it getting fired up to transfer the energy. Part of the latter is usually recovered when the system achieves a steady state or shuts down.
So let's say the V-belt connects an electric motor to a lathe. When you start the motor it revs up from nothing to it's nominal speed and during the transient interval while it's accelerating it stores energy in the mass of it's rotor, the stretch of it's V-belt and the mass of the rotating chuck and any workpiece attached to it. That's momentum for you...
Once it's all up to speed (and before you start cutting) the belt stretch is recovered and the energy stored in the rotor and head is constant and it's only drawing enough power from the line to cover friction.
For simplicity let's say that this is the '40s in New England and the circuit is DC. Naturally when you close the switch the motor has no back EMF and looks like it's DC resistance causing a large initial current to flow. Electricity can't stretch like the belt so it stores it's transient energy, it's momentum, by emitting photons which form a magnetic field around the conductor. Like the belt, as the load stabilizes they more or less snap back to the moving electrons returning most of the start-up transient.
I hope this helps a little, it's off-the-cuff so if it doesn't make sense (or it's wrong) it's my fault...
Regards, Rick
Just what exactly do you want our thoughts on?
How does an AC signal get from the source to the load through wires?
How does an AC signal get from the source (preamp) to the load (power amp)?
Quote. (Audiogon Herman)
In audio we are talking about the transfer of energy in the form of an electromagnetic wave.Electrons and wires are not needed to transfer this energy. For example, the waves will radiate in free space or down a waveguide.
Current is the flow of charge, not electrons; however it is not needed to transfer the energy therefore the current (flow of charge) in the wire is an effect, not a cause.
At low frequencies like audio it is easier to construct a system where the energy follows a wire more easily than through space or a waveguide because the wavelength is so long and the waveguide or antenna would need to be humongous.The water flow analogy is fatally flawed, it cannot explain everything that is happening with AC or DC. http://en.wikipedia.org/wiki/Hydraulic_analogy
Current flow is a misnomer with AC and causes great confusion since the charges are not really flowing. The periodic motion of the charge is not a flow in the conventional sense of the word. This is the only use of the word flow I have ever seen that describes periodic motion. For instance, pendulums do not flow. This basic misconception was the cause of much of the Audiogon debacle. Somebody was insisting that electrons vibrating about a fixed point could be described as current flow.
End quote.Thoughts?
Edits: 02/22/14
Well, first let me tell you flat-out that electron currents flowing in the wires is the mechanism that transfers all of the energy at DC (meaning the transient has "passed") and most of the energy in the audio band. That's just the way the world works regardless of what you may read on the Internet...
About electron mobility: Yes they actually can flow through metals and the oft used analogy with water in hoses isn't too bad. That's why we make wires out of metal! Metal atoms have weak outer valance's so elections can mosey about amongst them without much effort forming the eponymous "electron cloud" within the wire while keeping each other at arm's length, it's a "likes repel" thing...
If an external voltage, say a flashlight battery, is applied between the ends the wire then electrons are forced in from it's negative terminal and sucked out by it's positive terminal.
Since the wire is packed with free electrons they move virtually en masse transporting the applied energy to the other end at a good part of C. Note that the ones being forced out are NOT the same ones just flowing in, rather they are some of the resident crew that happened to be at the far (the positive) end so the energy propagation time is fast even though the individual electrons aren't.
The current flow does create an electromagnetic field of photons which actually doesn't do much at audio frequencies because the charge accelerations are slow and that's what drives radiation.
Rick
IN A SIMPLE CIRCUIT,
WHERE DOES THE ENERGY FLOW?
A Collection of Diagrams
12/2000 William Beaty BSEE
Electronics students commonly assume that electrical energy flows inside metal wires. Physics students know differently! Electrical energy normally doesn't flow inside of metals. In fact, the joules being sent out by batteries and generators are located in empty space: they take the form of electromagnetic fields surrounding the wires. The diagrams below will show us the details.
While a coil can store energy in the magnetic field outside its windings, and while a capacitor can store energy as an electric field in the insulating layer between the metal plates, an electric circuit handles energy a bit differently. As a whole, an electric circuit does both at once: it's both a coil and a capacitor. It's a capacitor because an e-field exists between the two halves of a simple circuit at different potentials. And it's a coil because a magnetic field surrounds each current-bearing wire. The shape of these fields will demonstrate that the EM energy which flows across a circuit is not stuck to individual electrons, nor is it moving along with the slow electrons within the interior of the metal wires. Instead the EM energy flows rapidly through the space surrounding the metal parts of the circuit.
For example, whenever a battery powers a light bulb, the battery spews electrical energy into space. That EM field energy is then grabbed firmly by the wires and guided by them. The field energy flows parallel to the wires, and eventually it dives into the lightbulb filament. There it drives the metal's population of movable charges forward, against the resisting force of electrical "friction." Electrons in the metal momentarily speed up before colliding with tungsten atoms. In this way the electrical energy gets converted into thermal energy. As a whole, an electric circuit is like a duct for electrical energy, but this duct has no walls.
Quote.
The speed at which energy or signals travel down a cable is actually the speed of the electromagnetic wave, not the movement of electrons. Electromagnetic wave propagation is fast and depends on the dielectric constant of the material. In a vacuum the wave travels at the speed of light and almost that fast in air.
In the theoretical investigation of electric circuits, the velocity of propagation of the electric field through space is usually not considered; the electric field is assumed, as a precondition, to be present throughout space. That is, the electromagnetic component of the field is considered to be in phase with the current, and the electrostatic component is considered to be in phase with the voltage. In reality, however, the electric field starts at the conductor, and propagates through space at the velocity of light (which depends on the material it is traveling through). At any point in space, the electric field corresponds not to the condition of the electric energy flow at that moment, but to that of the flow at a moment earlier. The latency is determined by the time required for the field to propagate from the conductor to the point under consideration. In other words, the greater the distance from the conductor, the more the electric field lags.[1]
Since the velocity of propagation is very high — about 300,000 kilometers per second — the wave of an alternating or oscillating current, even of high frequency, is of considerable length. At 60 cycles per second, the wavelength is 5000 kilometers, and even at a hundred thousand Hertz, the wavelength is 3 kilometers. This is a very large distance compared to those typically used in field measurement and application.[1]
The important part of the electric field of a conductor extends to the return conductor, which usually is only a few feet distant. At greater distance, the aggregate field can be approximated by the differential field between conductor and return conductor, which tend to cancel. Hence, the intensity of the electric field is usually inappreciable at a distance which is still small compared to the wavelength. Within the range in which an appreciable field exists, this field is practically in phase with the flow of energy in the conductor. That is, the velocity of propagation has no appreciable effect unless the return conductor is very far distant, or entirely absent, or the frequency is so high that the distance to the return conductor is an appreciable portion of the wavelength.
Please click on to the link provide below. Copy right prevented any copying of the text.
Go to Chapter 1 , page 4), 1.9 Fields. Follow through page 5
A photon is a particle without mass,,,Like a graviton...
Electromagnetic waves are particles and waves. But when they act as particles what kind of particles are they? Hint: electromagnetic waves move at the speed of light in a vacuum.
Electromagnetic waves are particles and waves. But when they act as particles what kind of particles are they? Hint: electromagnetic waves move at the speed of light in a vacuum.
And, generally speaking, in the case of a closed circuit the electrons in a conductor move as slow as thick molasses down the wire.Agree?
Disagree?
Why?
Edits: 02/25/14
If one goes so far as to measure wire with appropriate gear, one finds the propagation speed is set by the repeated series L and parallel C effect of a long set of conductors. Once a set of wires is approaching a wavelength or more, it is / has transitioned into what in engineering is called a transmission line. Unless your 'Ma Bell or installing an antenna, you never deal with cables long enough to be transmission lines.
In coax cable (at radio frequencies all the aspects of cables are much more important as they increase in importance / magnitude with frequency) they often specify the "propagation velocity".
Lets say you have a coax cable that goes around the earth and it has a PV of 66% (slow coax) and now you put a signal in at one end and waited for it to emerge at the other end, you would have waited about 2/10 of one second for the signal.
In other words, cable propagation speed is not an issue withing a living room.
Cables do have effects but these can be easily measured and the effect they have on the signal can be measured or auditioned by listening to the difference between one end and he other or the effect they have on the driving source.
If your concerned about electron flow, that view, consider a wire is like a ridged pipe full of water, if you force water in at one end, nearly instantly (at the speed of sound in water) that pressure reaches the other end. The speed the "electron pressure" travels is near the speed of light.
"If your concerned about electron flow, that view, consider a wire is like a ridged pipe full of water, if you force water in at one end, nearly instantly (at the speed of sound in water) that pressure reaches the other end. The speed the "electron pressure" travels is near the speed of light."
tomservo
Part 2 Demolition of a Myth
2.1 The basic misconception
The core misconception, propagated by many text books, is that moving electrons (or some other
form of current) in the connecting wires carry energy from the battery to the globe. I can give at
least five arguments why that idea is conceptually unsound. You may be able to think of more.
Objection 1 is that that electrons are just too slow to carry the energy fast enough! When the switch
is closed the light globe comes on almost at once. Many text books discuss a model of electrical
conduction in which a “gas” or “sea” or electrons is pushed slowly along a wire by an electric field.
If you know the density of electrons (the number of conduction electrons per volume of wire), the
diameter of the wire and a typical current you can work out how fast the electron sea moves along.
In a typical example of a 1mm copper wire carrying a current of 100 mA the answer turns out to be
about 0.01 mm.s-1 which is much slower than a tortoise. If those electrons were picking up energy
from the battery and then carrying it all the way to the light globe, you would have to wait an
awfully long time to see the globe light up.Objection 2 looks at AC circuits in which electrons don’t go anywhere much; they just jiggle back
and forth. So they can’t carry energy from one place to another. It would be silly to have a basically
different theory for AC and DC.
http://www.bing.com/search?q=http://science.uniserve.edu.au/schoo...002/sefton.pdf&FORM=HPDTLB&PC=HPDTDF&QS=n
Edits: 03/09/14 03/09/14
Is there a point in your reference that relates to what i said?
"If your concerned about electron flow, that view, consider a wire is like a ridged pipe full of water, if you force water in at one end, nearly instantly (at the speed of sound in water) that pressure reaches the other end. The speed the "electron pressure" travels is near the speed of light."
tomservo
If you are saying electrons travel through a conductor at near the speed of light then that is wrong according to the information I quoted from the Link.
If that is not what you meant I apologize and would you please further explain what you meant.
Jim
What I mean is, we transmit signals through wires and if we measure how long it takes from the time a signal goes into one end and comes out the other, one has a “propagation velocity” of that cable.
To picture the situation, imagine you had a pipe full of marbles form one end to the other. You force an additional marble in one end and nearly instantly, a marble is displaced at the other.
You can repeat this long enough until your first marble exits the far end if you want, but “that” time is not the propagation velocity of a signal.
http://en.wikipedia.org/wiki/Velocity_factor
http://www.picwire.com/technical/velocity_factor.php
The phrase "flow of electricity" refers generally to the movement of electrons (or other charge carriers) through a conductor in the presence of potential and an electric field. The "speed" of this flow has multiple meanings. In everyday electronics, the signals or energy travel quickly, as electromagnetic waves, while the electrons themselves move slowly.
This is what I have been trying to understand.
Would you agree, an audio signal traveling down a wire is energy in the form of an electromagnetic wave. The electromagnetic wave moves at near the speed of light. The electrons are basically just wiggling back and forth. (In an IC or speaker cable. No DC component in the audio signal.)
Do you agree or disagree?
When it comes to the speed of signal propagation the movement of individual electrons is irrelevant, as every electron is identical to every other electron. Even the existence of electrons is irrelevant to this discussion. (The presence of individual electrons does matter when considering thermal noise, but that's a different discussion.)
There is no need to go too far down the rabbit hole. It is necessary to stop at some point if one wants to accomplish anything. There are different levels at which subjects can be discussed, according, for example, to the knowledge and intelligence of the participants. This accounts for various explanatory scenarios that sometimes appear to conflict. In trying to get into a new technical subject, I have found it helpful to explore a range of books until I can find one that is at the right level to give me an effective learning experience, neither too difficult (incomprehensible) or too simplified (inaccurate and/or boring). Sometimes I have found it necessary to read through several levels of books before I could understand current research papers and sometimes I have given up the effort as too difficult for my talents and available time.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
You probably missed my post of a couple days ago on the subject of electron velocity in copper wire.
Why the games?
You agree with my posted message or you don't?
Get off the fence.
Who would disagree with your post. It's not as if it's breaking news. Are you trying to convert me? ;-)
Electrons move along at the leisurely pace of around one meter per hour in copper wire.
Electrons move along at the leisurely pace of around one meter per hour in copper wire.
Small steps at a time.The size of the wiggle
And about AC... how far do the electrons move as they vibrate back and forth? Well, we know that a one-amp current in 1mm wire is moving at 8.4cm per hour, so in one second it moves:
8.4cm / 3600sec = .00233 cm per secondAnd in 1/60 of a second it will travel back and forth by
.00233cm/sec * (1/60) = .0000389cm, or around .00002"
This simple calculation is for a square wave. For a sine wave we'd integrate the velocity to determine the width of electron travel.So for a typical AC current in a typical lamp cord, the electrons don't actually "flow," instead they vibrate back and forth by about a hundred-thousandth of an inch.
So for those that say an AC signal is moving/flowing back and forth in an IC connected to two pieces of audio equipment is wrong. The AC is not flowing back and forth, it is only vibrating. Correct?
Edits: 02/22/14
Incorrect.
The signal is not the same as the individual electron.
While each electron is merely vibrating the signal travels at near light speed.
With a little bit of imagination you can visualise this with the help of an executive toy like this:
http://upload.wikimedia.org/wikipedia/commons/b/b2/Newton's_Cradle.jpg
The signal, the part we are interested in, is the impulse while the 3 metal balls in the middle take the place of the electrons. The 3 center balls are hardly moving yet transmit the impulse (our signal) almost instantaneously ie the signal is flowing extremely fast whereas the 3 middle balls (our electrons) hardly move at all.
The signal is not the same as the individual electron.
While each electron is merely vibrating the signal travels at near light speed.
Yes, I agree.
I said.
So for those that say an AC signal is moving/flowing back and forth in an IC connected to two pieces of audio equipment is wrong. The AC is not flowing back and forth, it is only vibrating. Correct?
LOL, I sure screwed up that explanation.
Is this ok?
So for those that say an AC signal is moving/flowing back and forth in an IC connected to two pieces of audio equipment is wrong. The AC signal is not flowing back and forth, the audio signal is moving down the wire in the form of an electromagnetic wave from the source to the load.
Is that Correct?
Jim
You wrote,
"So for those that say an AC signal is moving/flowing back and forth in an IC connected to two pieces of audio equipment is wrong. The AC is not flowing back and forth, it is only vibrating. Correct?"
Hopefully there is no AC in an IC.
Hopefully there is no AC in an IC.
The signal is AC isn't it? Same for the output of a power amp?
ignore GK's attempt at semantic objections....LOL!
Stu,How about your comments on my original posted message.
The more I look the more info I find.
Example.
Understanding Electricity and Circuits:
What the Text Books Don’t Tell You
Ian M. Sefton
School of Physics, The University of Sydney
I.Sefton@physics.usyd.edu.au
Quote.
Part 1 IntroductionMost of the standard physics text books that we all know and either love or hate have some serious
deficiencies. My particular beef here is that, by trying to oversimplify some basic physics, those
books introduce or encourage some serious misconceptions and tell stories that are hard to believe.
For this discussion I have chosen the topic of simple circuits as exemplified by a battery and a small
torch globe – can we find a simpler circuit than that? I will use that example to explore some really
important physics that all school-level and most junior university-level texts omit and to confront a
serious misconception that can arise from studying those texts.
There are four main parts to this article. In part 1
I introduce the example and in part 2 we have a
look at the misconception about energy transfer
together with a quick summary of a better model.
In parts 3 and 4 we will examine the basic
physics in more detail and justify the alternative
model by applying the principles to the example
in more detail. For an overview of the problem
and its resolution you need only read parts 1 and 2.Part 2 Demolition of a Myth
2.1 The basic misconception
The core misconception, propagated by many text books, is that moving electrons (or some other
form of current) in the connecting wires carry energy from the battery to the globe. I can give at
least five arguments why that idea is conceptually unsound. You may be able to think of more.
Objection 1 is that that electrons are just too slow to carry the energy fast enough! When the switch
is closed the light globe comes on almost at once. Many text books discuss a model of electrical
conduction in which a “gas” or “sea” or electrons is pushed slowly along a wire by an electric field.
If you know the density of electrons (the number of conduction electrons per volume of wire), the
diameter of the wire and a typical current you can work out how fast the electron sea moves along.
In a typical example of a 1mm copper wire carrying a current of 100 mA the answer turns out to be
about 0.01 mm.s-1 which is much slower than a tortoise. If those electrons were picking up energy
from the battery and then carrying it all the way to the light globe, you would have to wait an
awfully long time to see the globe light up.
Objection 2 looks at AC circuits in which electrons don’t go anywhere much; they just jiggle back
and forth. So they can’t carry energy from one place to another. It would be silly to have a basically
different theory for AC and DC.
Please read the rest of the white paper.
http://science.uniserve.edu.au/schoo...002/sefton.pdf
Edits: 02/23/14 02/23/14
Define AC.
geoffkait,
Here is my answer.
You would guess wrong! It enforces the reason why solid core wire is directional imo. Especially when the nay Sayers give the reason why wire cannot be directional because the audio signal is AC.
Jim
have a grain structure which is basically the crystalline pattern of the substrate being aligned in a particular direction, generally in the direction of the cast metal or the drawn metal. You can change that structure by forging, annealing ( heat treatment) and use of cryogenics. But remember all metals are crystalline in nature ( except mercury) at room temperature. all crystals have an orderly or at least, semi orderly pattern, due to the formation of the crystalline structure and the nature of a crystal
Nt
If you can guarantee all bare strands of wire that make up the conductor are all aligned in the same direction as they were cast/drawn then yes, imo, the conductor would be directional.Problem is I doubt if any manufacture of stranded wire could care less if all the bare stands of wire within the conductor are going in the same direction.
Read unclestu's post above.
All metals have a grain structure which is basically the crystalline pattern of the substrate being aligned in a particular direction, generally in the direction of the cast metal or the drawn metal. You can change that structure by forging, annealing ( heat treatment) and use of cryogenics. But remember all metals are crystalline in nature ( except mercury) at room temperature. all crystals have an orderly or at least, semi orderly pattern, due to the formation of the crystalline structure and the nature of a crystal.
I agree.
Edits: 02/25/14 02/25/14
"If you can guarantee all bare strands of wire that make up the conductor are all aligned in the same direction as they were cast/drawn then yes, imo, the conductor would be directional."
I can actually supply a little actual experimental data here that supports your notion:
Over a decade ago I got the bit in my teeth to play with interconnects to try and get better performance and have some fun. Sparing you all the gory details and iterations I ended up with ~300ohm transmission lines composed of four strands of #28 magnet wire stuck in between two strips of masking tape with the grounds near the outer edges and the hots near each other in the center.
And they ended up a little directional, not a lot, but you could hear the difference. Since I built them I knew that they were symmetrical and also I knew that all four wires came off the spool in the same direction. The difference was audible in things like vocal sibilance, was it clear or 'spitty'. It's hard to describe sound but you prolly get the idea.
Obviously the thing to do was to build an identical cable alternating the wire directions in both signal and ground. So I did and the directionality went away. BUT I still preferred the sound of the directional design when installed in the 'right' way. So I just built them that way, drew an arrow on them so I know which end was the spool and have been happy ever-after.
I'm a technical sort and understand clearly that I don't understand clearly. Conversations with Stu years ago and simple reason convinced me that the most likely effect is due to the draw direction affecting the wire's crystalline structure in some manner.
The next step of course would be to see if both signal and ground direction mattered or if just one. But since I was happy with the sound and don't mind arrows on my cables I've just been building them that way ever since...
I'd say that this experience is likely appliccable to stranded wire but that the differences in it might not be as noticeable especially of it's of the bare, twisted variety, due to the possibility of strand interactions.
Regards, Rick
The next step of course would be to see if both signal and ground direction mattered or if just one. But since I was happy with the sound and don't mind arrows on my cables I've just been building them that way ever since...
rick_m
Hi Rick,
Here is a post from the late Bob Crump on the directionality of solid core wire.
Posted by rcrump on September 30, 2000 at 06:45:41
In Reply to: Re: maybe rcrump... I don't know, but... posted by Greg R. on September 29, 2000 at 19:47:48:
Solid core wire is extremely directional so just mark the end with some masking tape as it comes off the spool. Orient the wires so you have piece of masking tape at either end and terminate the wires. Throw it on a MOBIE or whatever overnight and then listen to it noting which way gives the highest image height. This is the correct orientation.
If you run the signal and return wires in the same direction you will end up with hot spots in the stage, normally at or close to the speakers, low image height and have a gaping hole in the middle of the stage...Keep in mind I am referring to the sound of the stage (reflections) not the individual instruments spread across the stage....Interconnects or speaker wires that have pianos wandering all over the stage normally have their signal and return going in the same direction....
Jim
"Interconnects or speaker wires that have pianos wandering all over the stage normally have their signal and return going in the same direction...."
Jim, I've never actually tried that configuration and haven't noticed the problems that he mentions. The only two that I've tried were with signal and ground running in the same direction and signal and ground running in both directions (remember I'm using four wires).
It was long ago and I made the unusual (for me) decision to do it all empirically just for fun. Part of that was that I suspected nothing would come of it, part that I figured it would be hard to quantify and part was that I didn't want it to feel like I was "working".
Now that I'm well retired I may revisit it and see is I can gleen any useful insights by attempting to find correlated measurements and models. It's also fun to understand things...
Regards, Rick
You would have to look into manufacturing process and supply chain issues. It would seem likely that there will be batches where all the strands go the same way.
My bet is you could find a manufacturer who cared if you paid enough $$$$.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
You wrote,
"Read unclestu's post above.
"All metals have a grain structure which is basically the crystalline pattern of the substrate being aligned in a particular direction, generally in the direction of the cast metal or the drawn metal. You can change that structure by forging, annealing ( heat treatment) and use of cryogenics. But remember all metals are crystalline in nature ( except mercury) at room temperature. all crystals have an orderly or at least, semi orderly pattern, due to the formation of the crystalline structure and the nature of a crystal."
I agree."
Who wouldn't agree? I thought everyone knew that.
You wrote,"Read unclestu's post above.
"All metals have a grain structure which is basically the crystalline pattern of the substrate being aligned in a particular direction, generally in the direction of the cast metal or the drawn metal. You can change that structure by forging, annealing ( heat treatment) and use of cryogenics. But remember all metals are crystalline in nature ( except mercury) at room temperature. all crystals have an orderly or at least, semi orderly pattern, due to the formation of the crystalline structure and the nature of a crystal."
I agree."
Who wouldn't agree? I thought everyone knew that.
geoffkait (M)
> > > > > >I said
"If you can guarantee all bare strands of wire that make up the conductor are all aligned in the same direction as they were cast/drawn then yes, imo, the conductor would be directional.
Problem is I doubt if any manufacture of stranded wire could care less if all the bare stands of wire within the conductor are going in the same direction."
Before I said,
"Read unclestu's post above.
"All metals have a grain structure which is basically the crystalline pattern of the substrate being aligned in a particular direction, generally in the direction of the cast metal or the drawn metal. You can change that structure by forging, annealing ( heat treatment) and use of cryogenics. But remember all metals are crystalline in nature ( except mercury) at room temperature. all crystals have an orderly or at least, semi orderly pattern, due to the formation of the crystalline structure and the nature of a crystal."
I agree."
geoffkait, you need to learn to read the whole post and not just pick and choose parts of the post that fits your fancy. You need to learn to keep in mind the main subject matter of the post.
> > > > > > >geoffkait (M),
Do you agree? Or disagree?
Edits: 02/25/14
It is interesting to visit certain cable manufacturers website. MWS is a good one: they have photos of the wire drawing process and helps better understand the mechanical nature of the manufacture. In addition most stranded wire is spooled and then various spools are combined to make the finished wire, so essentially the wire is unidirectional.
One must also take into consideration cross contamination. Dies used for silver for example and then used for sopper will carry traces of the silver. In addition wire as it is being drawn is lubricated, with something akin to cutting fluid. You can clearly see this in a few of the MWS machines where the wire under manufacture goes through a lubricating bath. that surely imposes impurities and further probably affects the grain structure.
Some wire manufacturers use jeweled dies (diamond or Sapphire) as little or no lubrication is needed and the jeweled die can impart a mirror like finish on the metal wire. Try looking at standard wire under a microscope, the striations from the die are clearly visible for the most part. Meticulous manufacturers maintain separate dies for different metals being drawn. That being said most outsource their wire from one the few wire giants: Belden, etc.
Here is what Belden has to say about directional cable:
Directionality, or the idea that electricity flows better in one direction through a cable than the other, is a common concept among certain self-identified audiophiles. Belden did a double-blind test for cable directionality in conjunction with an audiophile magazine. The end result was perfectly random. Belden is still happy to manufacture and sell directional cables to enthusiasts. They make up a long length of cable, cut it in segments, identify the ends of the segments so they know how it came off the spool (length A-> B, length B-> C, length C-> D, etc), and then let the customer identify by careful listening which direction is "better". Over thousands of cables sold, the chosen "best" signal flow is random, for segments cut from the same spool!
What was the test procedure? Who were the test subjects? When a magazine like Stereophile has reviewers who can not hear the mixed phase in many of the speakers they review, you think I would believe they can hear directionality differences?
Plus, They really and actually tested thousands of samples?
I somehow doubt that figure.
I have tested tens of samples over many spools being a dealer. I can consistently hear differences. For many, the differences are rather small, sometimes insignificant for some, but I can still hear them. For me, the difference is important enough to always code the ends.
and of course YMMV
You, as well as everybody else, hear what you subconsciously believe you should hear unless you do a double blind test. Unless you've done that anything you believe you heard is no more than an anecdote.
On another note: Logically if AC signal cables were in any way directional the signal, when reaching its destination, would have to be grossly distorted.
On another note: Logically if AC signal cables were in any way directional the signal, when reaching its destination, would have to be grossly distorted.
Why?
To be directional the cables impedance/resistance would have to be greater in one direction than the other.
Or if you think in terms of vibrating electrons imagine a cable running from left to right.
The electrons would be freely moving to say the right but would have to be restricted in their movement to the left or vice versa.
An extreme case would be a diode: Near zero impedance in one direction, near infinite impedance in the other. If you feed an AC signal through it the result is nothing like the original waveform since half of it would be completely missing. A truly directional cable would have to have a similar although lesser effect resulting in gross distortion.
You wrote,
"To be directional the cables impedance/resistance would have to be greater in one direction than the other."
It is. Just like fuses.
if the impedance is different in the two directions, then this can be measured. Measurements are not the end, they are a means to the end, which is good sound. Where measurements are available they can be quick and reliable. Listening tests tend to be unreliable and costly. If one is trying to improve the sound of a product (or a system) working by listening tests will be slow and costly. If effective measurements are available then much of the journey can be done quickly, with fewer expensive listening tests required.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
You wrote,"if the impedance is different in the two directions, then this can be measured."
I never said or even suggested that it couldn't be measured. Of course, nobody actually does measure it.
You also wrote,
"Measurements are not the end, they are a means to the end, which is good sound."
OK, if you say so. Are you volunteering? Measurements of what, that is the question. In this day and age, there are a great number of things that cannot be measured, or at least one would have difficulty coming up with a measurement strategy. You know what I'm talking about.
You also wrote,
"Where measurements are available they can be quick and reliable. Listening tests tend to be unreliable and costly."
Really? I would think the opposite. Unless you already have the measuring equipment. Besides, you still have the problem with WA Quantum Chips, clocks, rainbow foil and all those other things that go bump in the night.
You also wrote,
"If one is trying to improve the sound of a product (or a system) working by listening tests will be slow and costly."
I actually don't think that's true. Not slow, not costly.
You also wrote,
"If effective measurements are available then much of the journey can be done quickly, with fewer expensive listening tests required."
How do you effectively measure a lot of the new fangled things that have popped up in the last twenty years? All the quantum stuff. All the PWB stuff. Let alone all the CD fluids, room tuning widgets, all the RFI/EMI doo dads, even vibration control stuff. Much easier to conduct listening tests.
Edits: 03/01/14 03/01/14
Stu: "For many, the differences are rather small, sometimes insignificant for some, but I can still hear them. For me, the difference is important enough to always code the ends."
You: "Logically if AC signal cables were in any way directional the signal, when reaching its destination, would have to be grossly distorted."
I'd say your "logic" has a few bugs in it. Stu has identified directionality as a subtle effect. You claim that if it isn't gross it's nonexistent. See the disconnect?
I've heard it and at least in that instance it was subtle, but like Stu I too thought it worth controlling-for as it was easy and free since I was building my own cables anyway. It was subtle enough that I just assumed that it would be tough to measure so I really didn't try. It was most evident in the sound of soprano sibilences.
Might be fun to look at further one day. I still have most of the same stuff around.
Rick
Vocal waveforms tend to be asymmetrical. I suspect if you carried on you would be able to show up the effect using a suitable test waveform. I would start by looking at amplitude spectrum plots.
Until you can get repeatably different measurements it won't be possible to investigate further as to more specific causes, e.g. whether directionality is in the cable itself, in the connectors, or in the results of the physical termination processes.
Fun for a rainy day?
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
"Fun for a rainy day?"
Could be. No shortage of pursuable stuff in home audio but we get quite a few rainy days...
Rick
In my system directionality is not subtle. Both for interconnects and fuse. Very pronounced.
"In my system directionality is not subtle. Both for interconnects and fuse. Very pronounced."
Interesting. I didn't really test across systems. Have you tried to sort it out at all?
Rick
Not sure what you are referring to. Please elucidate.
"In my system directionality is not subtle. Both for interconnects and fuse. Very pronounced."
That should make it easier to "sort out", i.e. figure out the mechanism, than it would be if the effect were more subtle. Usually the grosser the effect the more likely it's readily measurable...
Rick
We already know what the mechanism is. And we've known it for twenty five years. Hel-loo!
"We already know what the mechanism is. And we've known it for twenty five years. Hel-loo!"
Gosh... That's wonderful. Help an old guy out, what was it again? I can't wait to pour over the supporting data and all...
R.
Roughly a couple of years ago I played around with a 75 ohm RG6 copper solid core quad shield coax cable to see if it was directional. I did not have any true 75 ohm RCA plugs. I just used a pair of Vampire RCA plugs I had. For the length of the cable I used the accepted 1.5 meter length. I think I made it just a tad longer.I used the digital out on my ARCAM Alpha 9 CDP connected to a Cambridge DAC Magic.
I first powered up my system and let it warm up for about 30 minutes. I picked CDs I was familiar with. For critical listening I like to use CDs with female vocals and parts with piano solos.
Just going from memory I played Diana Krall, "The Girl in the Other Room" and "Love Scenes". I also like to use Jenifer Warnes, "The Hunter" and "Famous Blue Raincoat".I did not pre burn in the cable. I did not want any settle in time on the cable.
The test.
I sat down for a listen.
I picked a track and listened only to a particular part over and over 2 or 3 times to train my ears to what I was listening to.
I then flipped the cable end to end and listened to the same part of the same track again.
Long story short the differences were not subtle.It was quite easy to pick the direction that sounded best to me on my system.
Once I found the direction that sounded best to my ears I then took a fine point sharpie pen and put a small dot on the cable end that connected to the DAC. I wanted it to be hard to see.
Next listening test was to listen to an entire track of a CD. Time after time I could pick/identify the direction that sounded best to my ears.
Next test, I took the cable down to an audio dealer I know quite well.
I talked to a salesmen I have known for many, many, years and asked him to listen to the cable. I did not say anything to him that might influence his listening experience. I just told him I had made the cable from a piece of RG 6 coax cable I had.
Long story short he picked out the direction that sounded best to his ears 100% of the time. The direction he liked best was the same as I had picked.
I should note this guy is not really into cables. He couldn't believe the coax cable could be directional.Before I left the Store I looked at a 2 meter Tributary digital cable hanging on a wall display. That’s right I said Tributary. Supposedly tributary’s best digital cable. I asked the salesman is the cable directional. He replied no. I asked him are your sure? He looked it up in a Tributary book and replied nope the cable is not directional. I said let me take it home for a week or two for an audition.
Well guess what? The digital coax cable is directional. And the center conductor is solid core copper. Again I marked the end of the cable that sounded best to my ears that connected to the DAC for a reference. I kept the cable for at least 2 weeks.
Back to the Dealer's store I went.
Long story short the salesman picked the correct direction 100% every time.Scientific test? No....
.
.
.
.
.
The revelation that digital interconnects and their direction can introduce large differences in measured jitter was quite a shock. The differences heard between digital interconnects—and in their directionality—have now been substantiated by measurement.
http://www.stereophile.com/content/transport-delight-cd-transport-jitter-page-9
Edits: 03/01/14 03/01/14 03/01/14 03/01/14
"Scientific test? No...."
Well...I don't agree, I think it was quite scientific and I'd say the odds are long that your coax cable's direction audibly affects the system performance. It sounds like you made a reasonable effort to avoid bias and had no investment in which way was best, if either.
And you know, I don't remember if I ever tried reversing mine. I've got one link in particular that I definitely want to run a test on. It just never occurred to me.
There are all sorts of reasons for testing things, what sort of cook doesn't taste the sauce? It's the unexpected correlations that spice things up. It's one thing if adding salt to the stew affects it's flavor, quite another if doing so makes the screen door quit squeaking. It usually pays to be a good observer and that includes not wontedly ignoring things that weren't expected.
Rick
Rick,Did you read this?
The revelation that digital interconnects and their direction can introduce large differences in measured jitter was quite a shock. The differences heard between digital interconnects—and in their directionality—have now been substantiated by measurement.
http://www.stereophile.com/content/transport-delight-cd-transport-jitter-page-9
Quote from Stereophile article.
Conclusions
There is now no question that jitter in CD transports and digital interfaces affects digital audio sound quality. Not only do different transports and interfaces sound different, they produce varying amounts of jitter and have their own "jitter signatures," seen in the jitter's spectral distribution.Moreover, we can see that transport jitter goes right through the digital processor's input receiver (even the Crystal CS8412) and affects the amount of jitter at the DAC's word clock—the point where jitter makes an audible difference. If the word-clock timing is different, the sound will be different.
The revelation that digital interconnects and their direction can introduce large differences in measured jitter was quite a shock. The differences heard between digital interconnects—and in their directionality—have now been substantiated by measurement.
Although the CD-transport measurements presented here are fascinating, it is impossible to draw conclusions about how a transport will sound solely by looking at its jitter measurements. Based on the measurements and listening impressions of the Audio Alchemy DTI, we can confidently conclude that the jitter differences the DTI imposes on both high- and low-jitter sources are easily audible, and that lower jitter always correlates to better sound. But when examining the jitter performance of other transports, a direct correlation is less clear.
Edits: 03/02/14
"Did you read this?"
Probably... back when. I shall, again?
Thanks Jim
Rick
You were probably napping when it was discussed. A search of the archives might turn up something, who knows?
Ah, the AES connection. Now, that makes sense!
:-)
Since you ask, I'd say you're guessing.
You wrote,"You would guess wrong! It enforces the reason why solid core wire is directional imo. Especially when the nay Sayers give the reason why wire cannot be directional because the audio signal is AC."
I wouldn't use those words, that "it enforces the reason why solid core wire is directional." What it would do is counter the argument for non-directionality. But only for the interconnects and speaker cables and for fuses not in the path of AC power. We still have the power cord and the fuses in the path of AC power in the amp and CD player, etc. Are they directional, too? If they are, the argument regarding the music signal and the electromagnetic wave do not hurt the naysayers' argument regarding AC.
Edits: 02/24/14 02/24/14 02/24/14
Nt
geoffkait,
Sounds like I best give you a technical answer
Quote
While most single-channel analog signal transmissions use direct current (dc) variations in current or voltage to represent a data value, frequency variations of an alternating current (ac) also can be used to communicate information. In the early 19th century, Jean Baptiste Joseph Fourier, a French mathematician and physicist, discovered that ac signals could be defined in terms of sine waves. A sine wave is described by three quantities: amplitude, period, and frequency. The amplitude is the peak value of the wave in either the positive or negative direction, the period is the time it takes to complete one cycle of the wave, and the frequency is the number of complete cycles per unit of time (the reciprocal of the period).
Now a question for you.
Is the output of a tube amplifier's output transformer AC or DC?
> > > > > > > > > >
geoffkait,
I would appreciate your help on my original posted message. I would think you of all people would be interested in the subject.
Jim
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