As electrons pass from one adjacent to another, it is obvious that a shorter cable will give a quicker sound, with more prat.
It was already stated in the book of reference by Dr Snakeoiler in 1793, « The fantastic travel of electrons ».
If we were considering DC, then possibly some form of unidirectional preference arising from crystalline structure might exist, akin to semiconductor behaviour, however audio is AC
I think that is right - I remember reading somewhere that the time it takes for an electron to go through a length of wire is quite appreciable - Millimetres per hour. Charge, however, moves really fast. I mean, you think that a Testarossa is fast, but it is a snail in comparison.
très drôle
If electrons do move, even slowly, then doesn’t that change the molecular structure? So does the conducting wire change in some way? Is that why cables only last so long - they disintegrate? We need Mr Tesla to explain.
Um - no, no change in the molecular structure. Electrons are constantly shared between atoms in many situations.
In a typical domestic DC circuit, an electron moves around a millimetre per second, or even less.
In AC circuits, the electrons simply jiggle one way then the other 50 or 60 times per second, depending on where you are in the world.
Talking about the speed the charge moves at compared to the electrons is meaningless - the electrons are the charge! You might have meant to say that the electrical effect travels very fast - a good fraction of the speed of light would be typical.
Talking about electron flow altering the metallic structure reminds me of a teacher years ago who told their pupils to put back wires after every electricity practical in the rack with both plugs connected together, ‘otherwise the free electrons dribble out of the free dangling end and the wire loses its conductivity’. Some pupils even believed him…
Mark
Well, yes, the electrons are the charge carriers. But they don’t move far even with DC. It’s a little like if you had a line of hard balls, all touching, and you hit a ball at one end of the line. None of the balls moves far, but the effect moves through the line very quickly.
What about DC offset/bias.
Not present normally in analogue audio interconnect or speaker cables.
That only depends on how long you leave the current running for. With a drift velocity of 1 mm/s, leaving a DC current running for an hour would mean each conduction electron would travel 3.6 metres, assuming it didn’t meet anything tricksy like a chemical cell first.
They collide with each other and the lattice ions with enormous regularity, as you imply, but they do also make long term progress, if given the chance.
Not that anny of this helps explain directionality!
Put a voltmeter set to DC across the speaker terminals of a Naim amp.
You might be surprised.
Yes, it’s normal for there to a bit of DC.
But actually there shouldn’t be… though that said, whilst ideally it should be none would expect none I’ve no idea what low level might be typical, nor what different manufacturers take as their tolerance.
Significant DC would indicate either a fault or bad design or adjustment, will affect the available excursion on bass drivers and if they have none-linearity at high levels will bring that in at lower levels, while if active multi-amping can result in burnt-out tweeters which have much lower power voice coils…
However, DC offset potentially (pun not intended!) could be either polarity, so if that is causing a cable to exhibit directional behaviour, it would mean the polarity of the offset would need to be checked to decide which direction to connect the cable…
From my distant memory of building hifi amps, you set the bias at the output transistors up so that there is a quiescent current.
There are no molecules of copper.
Just a lattice of atoms that each have 29 protons and 35 neutrons in the nucleus, with 1 associated electron.
The Standard Model (of particles) includes an electron (the smallest unit of the electron field?) and a photon (the smallest unit of the EM field).
How do these two fields interact (e.g. in an electrical wire)?
Once you’re into the Standard Model, classical (ie. pre-1900) physics doesn’t apply.
In an SM model, an accelerating electron results in the emission of a photon as a result of a disturbance in the electric field. Anything more detailed than that requires the sort of mathematics that would make a brave person weep.
Mark
That’s not the usual way they’re described. There’s no such thing as an electron field: a stationary electron simply creates an electric field around itself, rather like a stationary magnet produces a magnetic field around itself.
The photon isn’t the smallest unit of the EM field; in technical terminology it’s the gauge boson for the EM field, that is, it’s the particle that is used to model EM interactions between charged particles.
Again, anything more detailed than that will result in either tortuous sentences or tortuous mathematics.
Mark
Wonderful stuff. However after 200 posts is it possible to come to a conclusion on the original question? I would love to hear that my cables are indeed the wrong way round.
Edit. I guess “hearing” is the right word