High performance replacement ac cables

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mcullinan

Re: High performance replacement ac cables
« Reply #40 on: 23 Feb 2008, 03:22 am »
The great thing is Mike is saying Fck it Im still gonna drink this beer!
Thats some one who is focused on gettin the job done.
Mike

ecramer

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Re: High performance replacement ac cables
« Reply #41 on: 23 Feb 2008, 06:14 am »
And to think there's no photo shop involved with that picture  :lol:

Bigfish

Re: High performance replacement ac cables
« Reply #42 on: 23 Feb 2008, 02:14 pm »
LOL, a reenactment of Deliverance!

Ken

mcullinan

Re: High performance replacement ac cables
« Reply #43 on: 23 Feb 2008, 04:57 pm »
LOL. Im crying on the inside and humping on the outside...
Mike

satfrat

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Re: High performance replacement ac cables
« Reply #44 on: 23 Feb 2008, 05:10 pm »
LOL. Im crying on the inside and humping on the outside...
Mike

Funny I don't feel your pain as much as I do Toprounds,,,  :slap: :lol:

kyrill

Re: High performance replacement ac cables
« Reply #45 on: 26 Feb 2008, 11:49 am »
kilometers length of wire between the power plant and my house is also a big resistance to all voltages
So all the minute RFI and whatever EMI the wire picked up "outside" didn.t reach my house because of this wire resistance

which "length of wire" is relevant can be deducted by every EE. take a choice i say anything less than -110db is "irrelevant" the 0db voltage is 2 Volts how much is -110db? But even this low -110 db can be a wrong choice. -110db noise is irrelevant but can this and lower levels still negatively influence the musical signal as human ears perceive it?

So the last (tens?) metres to my equipment becomes important or maybe not

and the local pollution that can be picked up. then i wouldn't be surprised if all the properties of a good IC is also important for the AC cable. there is a different in voltage and amperage and nothing more. So dielectric constants, silver wire sound vs copper and so on colors the ac "signal" as well next to locally  picked up RFI and EMI. then the amp multiply this basis curent where all music will be made from. So in a sense the amp has two inputs the AC and the music signal. it blends the two together and multiplies it.

and a dead silent tweeter proves nothing. dirt. which by itself  does not "move" the tweeter, can still colours the sound as a "strange" cloud, robbing a bit transparency adding a  kind of unpleasant grain which does not reveal itself like noise at all

So i do hear AC cable differences to my surprise and not subtle too

I didn't expect to hear a difference between Signal cable shielded AC cable and the blue circle non shielded but twisted cable, so i did not do a comparison. By accident i notice than one balanced transformer sounded more transparent, more quick than the other which is exactly the same type of transformer. So i was puzzled. then i saw one had the Blue Circle the other signal cable.. I reversed the cables and the other transformer sounded more open
In my system the signal sounded more open and transparent

plz be aware that above story is my narrative as a non EE. It is a metaphor :green:

as a non EE i trust my intuition  :green:
I suspect that loosely braided ac cables ( not tried yet)  of many small copper or silverplated copper with a low(est)dielectric insulation ( Pe or teflon, or if you dare magnet wire with an airy cotton sock around them or cotton with a little beewax for naked wires) will sound better than the shielded ones.
metal shields  have very high dielectric constants
« Last Edit: 26 Feb 2008, 12:17 pm by kyrill »

jneutron

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Re: High performance replacement ac cables
« Reply #46 on: 26 Feb 2008, 02:09 pm »
So the last (tens?) metres to my equipment becomes important or maybe not

What is very important is the distance from the REFERENCE ground and the individual chassis.  All three prong cords set the reference ground at the wall outlet.

Using two dedicated runs from the breaker panel sets the reference ground AT THE PANEL.

The haversine plus modulation powerdraw the poweramp takes from the wall, creates an external, time varying magnetic field outside the cord..

Faraday's law of induction does all the rest using the ground loops.
I suspect that loosely braided ac cables ( not tried yet)  of many small copper or silverplated copper with a low(est)dielectric insulation ( Pe or teflon, or if you dare magnet wire with an airy cotton sock around them or cotton with a little beewax for naked wires) will sound better than the shielded ones.

Teflon is out, it creeps and will be dangerous.  Magnet wire insulation is too thin, and it is susceptible to damage and cracking from bending.  Socks and beewax, look up NFPA or NEC.  Do NOT recommend dangerous things such as this.

metal shields  have very high dielectric constants
I believe you meant to say, metal shields will have a high capacitance to the conductors as a result of the insulation's dielectric constant.

Cheers, John

kyrill

Re: High performance replacement ac cables
« Reply #47 on: 26 Feb 2008, 02:38 pm »
hi John thx for the corrections
with ground you mean not the Neutral and the hot? The yellow green wire?
however a lot of gear do not use the earth connection For instance my NAD receiver had a "blind/not connected IEC earth connection. Also Burson audio  does not use the earth in their poweramp and buffers, My Sony blue ray player also neglect the earth and so on

with respect to power cords yes magnet wire may crack if you bend it over and over so dont do it and i recomment another layer as a safety over it, paper, silk or cotton. I wil not dare to sell such a thing but in my own setup where i know "what is going on" i dont see a problem

ok last point

i have a wire naked, now pure air is its mantle.   the Electro magnetic force that travels with the current around the wire ( depending on voltage and Ampere) only how thick is "this" mantle?
Example 1 i take a wire with a very thin insulation, which is smaller in diameter than the EM force mantle, So the air around this thin insulator is seen by the EM force as part of the mantle around the wire. and this air will influence  positively the total dielectric property of this particular insulation.  that is maybe why they suggest to rise yr cable from yr carpet with wire raisers? So I  suppose the dielectric property will rise if you make this thin insulation layer thicker. That is why magnet wire has such low dielectrics?
Example 2 Now the second layer around this thin insulation is not air but a metallic woven fabric: the shield
On one hand it introduces capacitance between metal wire and shield, but on the other hand?
Will it adds a much  more higher dielectric than the air in the first example and will lower the total dielectric of the total mantle as if a composiet mantle has its "own" dielectric?

jneutron

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Re: High performance replacement ac cables
« Reply #48 on: 26 Feb 2008, 03:23 pm »
hi John thx for the corrections
with ground you mean not the Neutral and the hot? The yellow green wire?

I can only speak of electrical practice in the USA, and specifically, the East coast..

A 3 prong outlet has a hot, a neutral, and a safety ground.  Hot, we'll leave alone..

The neutral is the intended current carrying conductor in AC delivery.  The ground is NOT supposed to carry any of the load current.

At the main service entrance panel, in my neck of the woods, the neutral and the safety ground are bonded together inside the panel.  The street feed neutral outside the house is a steel wire which is mechanically connected to the house to support the two hots, and the street feed water pipe is connected to the same buss as the neutral.  Loss of the street neutral can wreak havoc with all appliances depending on the quality of the safety ground.  Loss of the safety ground due to corrosion or replacement of the street feed with plastic, will be dangerous should the neutral ever fail...Simple things such as appliance destruction, complicated things such as electrocution in the shower..

So even if you choose not to connect them at the equipment, they are that way in your house anyway.  If you were to measure the voltage potential between the ground and the neutral for an outlet, you will find that it is not zero volts, there is noise, lots of hash..

With respect to ground potential and noise, it is necessary to liken the entire house ground system to a 40 foot by 40 foot trampoline.  While it prevents people from falling (excessive voltages to ground), if one brings a gravel compactor on board, the entire trampoline vibrates.  This is the house ground...

We use the ground at the outlet as a grounding reference.. All equipment which has a ground lug will do the same.  But, two pieces of equipment with an IC, that forms a loop.  That loop can pickup magnetic field and generate voltages.  The drop across the IC shield will introduce into the poweramp, and cause an audible signal.  If it's hum, it is identified as such.  If it is signal caused by the current draw of the amp, it is not as easy to realize because the audio signal is masking it to some extent.  (loss of black background, which is not the same as silence between tracks).


however a lot of gear do not use the earth connection

Don't forget, even a two prong neutral ties to safety round at the panel.  So, the loop is even larger with no control.  Any capacitance from the xfmr to chassis will introduce error signals.  Any noise blocker like a common mode choke will present as a low impedance to hf hash, so the 2 prong cord will radiate moreso.
with respect to power cords yes magnet wire may crack if you bend it over and over so dont do it and i recomment another layer as a safety over it, paper, silk or cotton. I wil not dare to sell such a thing but in my own setup where i know "what is going on" i dont see a problem

In my neck of the woods, an insurance underwriter called in for an inspection cannot overlook such an obvious fire and electrocution hazard, even if that is not why they are there.  A fire inspector called by an insurance company for a fire claim, certainly would not overlook it.  An electrocution speaks for itself.

i have a wire naked, now pure air is its mantle.   the Electro magnetic force that travels with the current around the wire ( depending on voltage and Ampere) only how thick is "this" mantle?
Example 1 i take a wire with a very thin insulation, which is smaller in diameter than the EM force mantle, So the air around this thin insulator is seen by the EM force as part of the mantle around the wire. and this air will influence  positively the total dielectric property of this particular insulation.  that is maybe why they suggest to rise yr cable from yr carpet with wire raisers? So I  suppose the dielectric property will rise if you make this thin insulation layer thicker. That is why magnet wire has such low dielectrics?

The magnetic field will be independent of the dielectric.  For widely spaced wires, the e-field will be consistent with two conductors which are metal the diameter of the insulation cover.  As the wires get closer, the insulation DC will begin to impact the overall capacitance and e-field geometry.  Magnet wire has a thin dielectric coating to allow a higher metal to insulation packing factor for multiple turn entities such as inductors, transformers, and magnets.  Additionally, the coating is designed for fixed applications where movement is not a consideration..and finally, many coatings are high temperature capable to allow higher current densities without burning the insulation.

Example 2 Now the second layer around this thin insulation is not air but a metallic woven fabric: the shield
On one hand it introduces capacitance between metal wire and shield, but on the other hand?
Will it adds a much  more higher dielectric than the air in the first example and will lower the total dielectric of the total mantle as if a composiet mantle has its "own" dielectric?

This creates a coaxial system, the capacitance is determined entirely by the dielectric constant, the insulation thickness, the inner wire outer diameter, and the inner diameter of the shield.

Cheers, John
« Last Edit: 26 Feb 2008, 05:07 pm by jneutron »

Brown

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Re: High performance replacement ac cables
« Reply #49 on: 26 Feb 2008, 04:41 pm »
John very informative. Thanks for taking the time. Well done mate.


brown

kyrill

Re: High performance replacement ac cables
« Reply #50 on: 26 Feb 2008, 05:11 pm »
Hi John
plz forgive my  continueing questions

I understand the capacitance issue: "
This creates a coaxial system, the capacitance is determined entirely by the dielectric constant, the insulation thickness, the inner wire outer diameter, and the inner diameter of the shield."

I understood as a layman that  electricity "following" a wire cannot be represented by the use of a  metaphor of particles or water following a hollow tube, because a great part of the "electricity" follows the path alongside the wire.
so if you make those particles in the wrong metaphor tiny magnets all aligned, then you can imagine that outside this tube a magnetic field is traveling with the parts. The dielectric constant somehow interferes with the traveling of those outside tube properties of the electric current. A vacuum and less good,  air interferes least,  the higher the dielectric constantis of the insulation the more interference to those outside wire properties fo the electric current

now, besides the capacitance issue doesn't the metal shield not interfere with those properties of the "travelling electrons" ( if they travel) which are effected by the dielectric constant characteristics of the insulation?
dielectric constants effects can be heard as freq alterations but also as transparency, quickness, musicality and so on. Capacitance ( i can be wrong of course) is mostly heard as an alteration of the higher freqs. So can the metal mantle not only affect the freqs as is explained with the capacitance concept but also this "musicality, transparency and so on..?
« Last Edit: 27 Feb 2008, 01:03 pm by kyrill »

jneutron

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Re: High performance replacement ac cables
« Reply #51 on: 27 Feb 2008, 06:10 pm »

I understood as a layman that  electricity "following" a wire cannot be represented by the use of a  metaphor of particles or water following a hollow tube, because a great part of the "electricity" follows the path alongside the wire.

That metaphor is useful when discussion of the ampacity of the wires is involved.  People are more able to understand how a small hose causes a pressure drop when it constricts the flow (light a light guage wire), they understand how the flow goes from high pressure to low, like current caused by voltage..but those metaphors do indeed have limited use once past the simple aspects.

so if you make those particles in the wrong metaphor tiny magnets all aligned, then you can imagine that outside this tube a magnetic field is traveling with the parts. The dielectric constant somehow interferes with the traveling of those outside tube properties of the electric current. A vacuum and less good,  air interferes least,  the higher the dielectric constantis of the insulation the more interference to those outside wire properties fo the electric current

It's a far better visual to think in terms of propagation along the wire of a step function of voltage.  The leading edge runs down the wire at the prop speed..right behind the leading edge is current within the wires, it has charged the space behind it with magnetic energy from the equation E = 1/2 LI2..  At the leading edge, there is a current flowing from one wire to the other, this current is filling up the capacitance of the dielectric with energy to the tune of E = 1/2 CV2 .  Right behind the leading edge, the energy in the magnetic field is exactly equal to the energy within the electric field....this defines both the characteristic impedance of the cable, and the propagation velocity. (note: while the energy relationships and the prop speed consequences are intuitively obvious to even the most casual observer, I'll provide the derivation for the number crunchers...)

requisite math blurb:  you can turn away here if you don't have the stomach for this geeky stuff...

1/2 LI2 = E = 1/2 CV2

Get rid of the E

1/2 LI2 = 1/2 CV2

get rid of the 1/2

LI2 = CV2

put C on the left by dividing both sides by C

L/C I2 = V2

Divide both sides by I2

L/C = V2/I2

Take the square root of both sides

(L/C)1/2 = V/I

V/I is equal to R by ohms law, Z when we speak of a reactance...

This is the equation Z = (L/C)1/2, the characteristic impedance of a cable..

Now, the only way to affect the cable is by altering either the capacitance, or the inductance.  Shields and their proximity can affect both.

As to how to interpret your explanation, I'm kinda at a loss.  I go by the e/m theory stuff (as if that weren't obvious :duh:), so am having difficulty trying to understand your driving point.  :oops:

Cheers, John



kyrill

Re: High performance replacement ac cables
« Reply #52 on: 27 Feb 2008, 07:17 pm »
Hi John thnx for yr undertandings but but ;)

impedance, capacitance and inductance affects in the same "logic envelope"
"only" frequency and "loudness", no when listening to music?

But dielectric constants have a far wider range to be heard, NOT only frequency
things like musicality, transparency, wetness/graininess   placement, tone
( not the same as freqs)

my idea is that impedance, capacitance and inductance are not explaining enough
for differences to be heard. I wonder if molecular resonance plays a role, other variables
modernistic electrical science didn't explore as the electricity model seemed complete enough

So my idea is ( for whatever reason) that metallic mantles will negatively affects the
experience of sound if that is true, braided cables must sound somehow more musical, open and airy than shielded cables  ;)

jneutron

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Re: High performance replacement ac cables
« Reply #53 on: 27 Feb 2008, 08:06 pm »
Hi John thnx for yr undertandings but but ;)

impedance, capacitance and inductance affects in the same "logic envelope"
"only" frequency and "loudness", no when listening to music?

But dielectric constants have a far wider range to be heard, NOT only frequency
things like musicality, transparency, wetness/graininess   placement, tone
( not the same as freqs)

my idea is that impedance, capacitance and inductance are not explaining enough
for differences to be heard. I wonder if molecular resonance plays a role, other variables
modernistic electrical science didn't explore as the electricity model seemed complete enough

So my idea is ( for whatever reason) that metallic mantles will negatively affects the
experience of sound if that is true, braided cables must sound somehow more musical, open and airy than shielded cables  ;)

Molecular resonance, no.

That is the type of silliness that is made up by people to explain what they (or their target market) don't understand.  Grain boundaries, motor-generator, sub nanosecond jitter, many silly explanations are foisted upon unwary souls (in the context of this discussion, unwary souls are those without the technical background to call a ridiculous explanation as such).

Look at the OP's Q about AC line cords.  If one neglects actually understanding what a line cord does or is capable of doing, there is no viable explanation for a difference, there is no cause for the effect.    But in truth, when one examines the entire system and includes all the interactions (many which have been historically neglected or just missed), there are many reasons why a line cord can affect the system transfer function (sound).  Just because the engineering community at large has not figured it out in a direct line of reasoning doesn't mean there is no logical, mathematically deterministic explanation.  (for example, designing a balanced input amplifier that has excellent ground current rejection across the entire audio band eliminates ground loop issues.)

My explanation of ground loop affected by the line cord is only one such example.  There doesn't have to be audible hum for a ground loop to affect the sound... the external ground loop has a coupling response that is proportional to frequency, the internal amplifier sensitivity to that ground current is proportional to the frequency squared.. :duh:

The terms that you provide, ""musicality, transparency, wetness/graininess   placement, tone"", are all well and good, but they do not provide any clue as to what they mean in engineering terms..  Practically useless to an engineer, as they do not tie to their knowledge.  It doesn't mean that they are useless to you of course, it's just your (and others) descriptors.

Before embarking on a quest of "new physics" to explain something, it is absolutely necessary to characterize what it is we can hear first.  Localization (your placement, my image or soundstage) requires incredible levels of interchannel control, 2 uSec and about .05 dB, but this has been historically ignored within the audio engineering community..so they cannot actually define how well a stereo system can image a sound in space..  Isn't that the whole purpose of two channel reproduction?????? Isn't anybody awake???

I find the same type of missings in biwiring, speaker cable impedance, IC impedance, amplifier design and test...  But yet, without a criteria such as 2uSec control or .05 dB for localization parametrics, how would one design a piece of equipment to control for those parameters?  Right now, all I see is hit or miss....designers tossing "new or better sounding components" into the chassis without having a clue as to what is changing.  There is indeed an engineering explanation going on, but random substitution is not engineering, nor design.

Cheers, John





kyrill

Re: High performance replacement ac cables
« Reply #54 on: 27 Feb 2008, 09:41 pm »
ah well I understand and see where you come from John

and my "rational logic" can only give you right, to be honest .

but there are grey area's not completely illuminated by the assumptions EE logic
rest upon yet.

On the other hand until proven, it is unproven.
But how can you prove something you dont know about yet?
deductive reasoning can only prove the well known
inductive reasoning however needs to forget previous assumptions as they stand in the way
only then new theory can be generated

why do cotton insulators sound more natural than teflon which has a similar or even lower dieelectric?
Why does a silver wire mostly sound better than copper and probably less than a gold wire?
can that only be the effect of the resistance? Does resistance have a specific sound of its own except loudness?

ah well ;) i am not really questioning things

jneutron

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Re: High performance replacement ac cables
« Reply #55 on: 27 Feb 2008, 10:04 pm »
but there are grey area's not completely illuminated by the assumptions EE logic
rest upon yet.

I provided six examples of such.  They are grey because they have not been properly investigated, not because the technology does not exist, nor because logic failed.

Cheers, John

*Scotty*

Re: High performance replacement ac cables
« Reply #56 on: 28 Feb 2008, 03:20 am »
John,as near as I can figure the power cord affects the dynamic impedance of the power supply that it connects to the mains.
It has been my experience that a well designed, good sounding circuit always sounds markedly better with a low impedance wide bandwidth power supply. I think beginning to understanding the causes of the observed phenomena would require a dynamic test signal which would measure the bandwidth of the power cord as it is connected to the mains on one end and a power supply on the other end or at least a test setup with a power cord terminated on either end with the same impedance values as found under typical use conditions. Given the potential for multiple
non-linearities at every step in the chain of a typical audio system and the presence of the human factor it's no small wonder that there is no agreement about how power cords should be designed or what power cord would sound good in a specific system.
Some useful data might be obtained by by someone with the appropriate test equipment and the time to undertake the testing.
Scotty

jneutron

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Re: High performance replacement ac cables
« Reply #57 on: 28 Feb 2008, 02:47 pm »
John,as near as I can figure the power cord affects the dynamic impedance of the power supply that it connects to the mains.
It has been my experience that a well designed, good sounding circuit always sounds markedly better with a low impedance wide bandwidth power supply. I think beginning to understanding the causes of the observed phenomena would require a dynamic test signal which would measure the bandwidth of the power cord as it is connected to the mains on one end and a power supply on the other end or at least a test setup with a power cord terminated on either end with the same impedance values as found under typical use conditions. Given the potential for multiple
non-linearities at every step in the chain of a typical audio system and the presence of the human factor it's no small wonder that there is no agreement about how power cords should be designed or what power cord would sound good in a specific system.
Scotty

One needs to keep in mind the difference between causation and correlation.

A stiff supply everybody knows the benefits of. 

To make a cable low impedance requires reducing the L and increasing the C.  To make an 8 ohm cable for example, requires inductance in the 10 nanohenry/foot  range and capacitance in the 300 pf per foot range.

The textbook definition of inductance is:  The relation between the amount of energy stored within the magnetic field of a system as a result of current flowing through the system, that old E = 1/2 LI2, re-formed as :
L = 2E/I2.

The concept of inductive coupling is the ability of a conductor pair to receive the magnetic field that is being broadcast by another entity.  The best emitter is also the best receiver.  To reduce inductive coupling, one must reduce the transmitter and receiver inductance, or position them so that the field of one cannot become the field of the other..


The concept behind lowering the inductance of the cable, is to reduce the stored energy therefore the external magnetic field..  Reduction of the EXTERNAL stored energy within a line cord reduces the inductance..and also reduces the cord's impedance.  (reduction of the impedance by increasing the capacitance does not alter the inductive coupling...but it can stop RFI if there is any on the line that can affect the amp operation).  But again, some confuse blocking the RF with the cord impedance as cause.

Many people reduce the inductance of the line cord, and do not understand that as a consequence, they have reduced the "transmitter's" efficiency at affecting the input loop.  They mis-attribute the change in sound to the power cord affecting the power supply via the power delivery impedance, when really, that is a secondary effect; the first being the drop in input coupling.  If one shouts from the rooftops that the cord "fixes the power quality" in some fashion (typically with a silly made up physics explanation, they are incorrect and the EE types take them to task for that.

Causality vs correlation. 
Some useful data might be obtained by by someone with the appropriate test equipment and the time to undertake the testing.

Do not expect a power cord vendor to do this.  They would not be smart to destroy the advantage their marketing "floobydust" provides them...they have to pay the bills after all.  Complete modelling of line cord effects would eventually reduce aftermarket cords to the level of "jellybeans", and there is no profit in jellybean product.


Cheers, John