..yet another Wire thread:

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#22
Three minutes into this video I already have issue. His concepts with the chain and electrons is misleading. he is talking A/C as if it were D/C.
Electron movement is simply not as he describes and is motivated (EMF) by a change in EMF from positive to negative on the conductor.
The conductor is not moving like the chain so scratch THAT ENTIRE PORTION OF THE FIRST THREE MINUTES.
 
#28
I am still not sure about the following: does the energy move between the source and the load in a straight line down the shortest path edit: through space (the one meter or so in the clip), or does it follow the wires and goes all along them until it reaches the load?
 
#29
markgolf said:
Yeah I watched that late last night. Certainly eye raising and sure to spark debate.its implications on audio are interesting for one im thinking of raising my speaker cables off the floor maybe its not snake oil.
Mark
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Not much to debate, it's fundamental physics. Unfortunately the analogy of electrons flowing in wires like water in pipes, while useful for conceptualising electric circuits, is just that - an analogy. It is not representative of how electrical energy is actually transferred via conductors, no matter how logical and/or obvious it seems.

There's probably not a lot to gain in raising your speaker cables unless your floor is mu-metal, but there are implications for the design of speaker cables.
 
#30
He does seem to imply that the energy flows in a straight line between the battery and the bulb, down that short path of around 1 meter. But his answer doesn't seem dependent on the distance between the battery and the bulb at 1/c seconds. More correctly it is 1/(one length of the wire at light speed) seconds which doesn't take into account the physical distance between the battery and bulb. So it would take the same amount of time if you double the distance between the battery and the bulb, but at the same he implies it moves in a straight line over the space between the battery and the bulb. I'm a bit confused. I may have understood it wrongly as he phrased it.

edit: or maybe the 1 in 1/c seconds is the 1 meter distance between the battery and the bulb? So for two meters distance it would be 2/c seconds (with the same length of wire). which would make sense as if you totally stretch the wire then it would be c/c seconds, so 1 second for the whole length of the wire. that seems to make more sense.
2nd edit: yeah 1m/300000000(m/s) meters go away so you're left with seconds. so now we're back in magicland (for me). the actual energy moves in space in a straight line through the em field between the battery and the bulb irrespective of cable length. which is the real crazy thing for me out of all this. and the only thing the cable length (resistance) does is determine how much of the total power goes across the 1m to the bulb. so with very good cables most of the actual power goes over that short distance, while little spreads along the wire (wire which presents a small load).
 
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#32
To put some perspective on dimensions, for example in a cable with a velocity factor of 70% the transmission speed for electrical signals is approximately 200,000,000m/s. Thus the wavelengths of EM fields for 20Hz to 20kHz will be in the range 10,000,000m to 10,000m, or 10,000 kilometres at 20Hz shortening to 10 kilometres at 20,000Hz. A one metre distance will shift phase by 0.000036º at 20Hz and 0.036º at 20kHz. Note this is a simplification because the properties of permeability and permittivity that determine the velocity factor of a cable are frequency dependant, therefore the velocity factor of the cable is also frequency dependent, and so too propagation delay phase shifts.
 
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#33
johnmath said:
There's probably not a lot to gain in raising your speaker cables unless your floor is mu-metal, but there are implications for the design of speaker cables.
Click to expand...

I was particularly thinking of the cable connection to each driver (from crossover), which is a least in part - in close proximity to the magnetic field of the driver. (..and the interaction with "back" emf/current fluctuating the field (electrical and magnetic) with drivers other than tweeters.)
 
#34
The EM field associated with current flow in a cable is independent of or overlaid on the other EM fields and does not interact with them. Another conductor in the veracity of the that field with react to the sum of all the fields, and vice versa. The reduced strength of magnetic fields around coaxial and star-quad configuration cable is useful in reducing interaction between cables. For that reason I use star-quad, and sometimes coaxial, for loudspeaker cables, both between amplifier and loudspeaker and between crossover and drivers.
 
#35
markgolf said:
I think the big question is how big is that electromagnetic field? In the video it shows interaction between the source and load via the air as well as the conductor and I think that part is questionable unless very close.how big is the field around a conductor? I'm sure it depends on voltage and current.

Mark
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I think the question isn't how big the field is, but rather:

..is there any alteration in the field? (even if extremely small).
 
#37
This guy who made the video is so full of crap that's it's hard to know where to start. His analysis between 6:04 and 8:23 times on the video makes no sense at all. It just a bunch of gibberish using technical terms.

The magnetic fields surrounding wires as a result of the current through them is very weak as the distance from the wire increases. His analysis claiming the the battery itself transfers energy through space to the lamp is so absurd that it alone destroys any credibility that he might have.

This is garbage. Pay no attention to it.
 
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