The 3 original Cyril Bateman 'Speaker Cable' articles in Electronics World (United Kingsom) Magazine
Measuring Speaker Cables: 1 Cyril Bateman Dec 1996 page 925
https://worldradiohistory.com/UK/Wireless-World/90s/Electronics-World-1996-12-S-OCR.pdf
Measuring Speaker Cables: 2 Cyril Bateman Jan 1997 page 52
https://worldradiohistory.com/UK/Wireless-World/90s/Electronics-World-1997-01.pdf
Measuring Speaker Cables: 3 Cyril Bateman Feb 1997 page119
https://worldradiohistory.com/UK/Wireless-World/90s/Electronics-World-1997-02.pdf
These all seem older the the papers on the Wayne Kirkwood site.
Measuring Speaker Cables: 1 Cyril Bateman Dec 1996 page 925
https://worldradiohistory.com/UK/Wireless-World/90s/Electronics-World-1996-12-S-OCR.pdf
Measuring Speaker Cables: 2 Cyril Bateman Jan 1997 page 52
https://worldradiohistory.com/UK/Wireless-World/90s/Electronics-World-1997-01.pdf
Measuring Speaker Cables: 3 Cyril Bateman Feb 1997 page119
https://worldradiohistory.com/UK/Wireless-World/90s/Electronics-World-1997-02.pdf
These all seem older the the papers on the Wayne Kirkwood site.
Thanks.
Their explanation is no better. Why not just come out and say "inductance". Granted that is not as sexy as electromagnetic effects.
A power cord made of many smaller gauge wires is dangerous. If one conductor shorts, the smaller conductor may not be able to trip a breaker.
Jn
I do not challenge your statement. For the record it does not apply to this case in my humble opinion.
In fact one of the noteworthy observations was the off axis improvement in image clarity. I am not talking minor head movement in my listening chair, I am talking about a stable 3d image 10 feet off axis in another part of the 20x25 foot room.
And thanks, nothing said here will alter my enjoyment. Built, not bought btw.
Mmmmm, did you look at *any* power cord lately?
Electrical power wires are supposed to be as close as possible to a short.
Only cost and bulk prevent us from using real thick wire.
In any case, not sure what they would "short" to anyway.
And if you short a thin, highish resistance conductor, you are actually making its life easier.
Very colorful assortment. In the trays at work, all wires from multiconductor to 535kcmil are black jacket.
We use DLO, high strandcount for flexibility.
What I meant in regard to the wireworld power cables is that they use small gauge insulated wires to make a power cable. If for example (they do not) a power cable was made with 50 insulated 24 AWG wires by braiding hot and neutral, the inductance would be extremely low per foot and zero external magnetic field. The problem is, the cable would be very susceptible to physical damage, not something you want with a power cable.
WW seems to spiral them, so not quite as bad. But still, small individual conductors are more susceptible to physical harm.
Jn
What is being lost in everybody's argument is this:
The transmission line impedance at audio is not the concern. It is the RF impedance, but not because of RF. Just energy storage at audio frequencies.
The energy that is stored in the cable is stored by inductance and capacitance.
The relationship between the two is:
LC = 1034 * DC for coax and striplines (field constrained cables), DC being the relative permittivity of the insulation.
Or
LC= 1034 * EDC for unconstrained cables such as zip, EDC being in the 5 to 10 range based on conductor spacing and geometry.
Or
LC = 1034 * mu(r) * epsilon (r), (btw, L in nH per foot, C in PF per foot).
The energy within a cable is minimum when the inductive storage equals the capacitive storage.. the energy stored in the cable at audio frequencies and DC is absolutely dependent on the load impedance.
Starting with equivalence of storage:
.5 LI^2 = .5 CV^2
Move C and I^2....get rid of both .5 factors..
L/C =(V^2)/(I^2)
Sqr both sides...
Sqr(L/C) = V/I...sqr(L/C) is the RF transmission line impedance, V/I is the load impedance.
So when a cable has the RF characteristic impedance as the load, the cable energy storage is minimized.
Jn
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Everything is correct, according to any textbook for EE undergraduates. Only the causality to this topic is violated.
But what does this mean for someone listening to the sound coming from the speakers?
Simple. The delay is dependent on the ratio between the cable RF impedance and the driver impedance. Since the driver impedance can swing wildly even with just a sine sweep, the delay will also. If the variation rises to the 2 to 10 uSec swing, it might be audible w/r to imaging. Depends of course on what frequencies, as our imaging ITD sensitivity is very frequency dependent.
As I posted earlier, do the one channel two zip centering test, first with both zips intact then split one. If you do not hear any assymetry, there is nothing to "see", listen to some music and enjoy a beverage.
Jn
Luckily ITD ( Interaural Time Difference ) is about the lateral movement of a single mid-frequency sound. So no frequency change, no cable delay change.
I would think that many crossovers introduce much greater frequency related time differences.
* * * * * * * * * * *
Also Velocity of Propagation changes a whole lot at audio frequencies in a reasonable cable.
5,000,000 m/s @ 20HZ
125,000,000 m/s @ 20kHz
I would think that many crossovers introduce much greater frequency related time differences.
* * * * * * * * * * *
Also Velocity of Propagation changes a whole lot at audio frequencies in a reasonable cable.
5,000,000 m/s @ 20HZ
125,000,000 m/s @ 20kHz
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The test I mention does not care about the crossover, it first checks that both speakers are identical enough that the image in it's entirety is centered.
If splitting one zip changes that, next test. If nothing changes, move along nothing to see here.
The beauty of the test is it uses music, and if a motional dependent impedance shift causes a variation in ITD that is audible, this test will see it.
Also, it uses a center reference the listener can use to gauge image shift. The frequencies which are not ITD referenced will remain centered, the listener can discern more readily shifts of some content relative to others..
As to prop velocity, that is of no use within the discussion, just a red herring.
Jn
If splitting one zip changes that, next test. If nothing changes, move along nothing to see here.
The beauty of the test is it uses music, and if a motional dependent impedance shift causes a variation in ITD that is audible, this test will see it.
Also, it uses a center reference the listener can use to gauge image shift. The frequencies which are not ITD referenced will remain centered, the listener can discern more readily shifts of some content relative to others..
As to prop velocity, that is of no use within the discussion, just a red herring.
Jn
Can you provide a calculation of the delay based on a typical setup?
Also, why do you think a 10 us "delay" would be audible when you have phase wraps with LR4 crossovers that some people can't hear, and sometimes well over 30 ms group delay in the bass region that are generally inaudible?
Those parallel resistors taking the form of more copper, as in making cable thicker.
No news there.
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