Cable cooking

[Mundox]

Hello everyone.
I hope this is the right place to post this.
I have witnessed a heated arguement between a group of Audiophiles and sound engineers about the effects of cable cooking in Audio Systems.
There's also cable cooking devices available.
Having no experience about the subject I am alo curious to see what design gurus here think about it. This is a trusty place I refer from time to time for technical advice.

Does it have a scientific ground?
Or is it something un-explainable?
Or is it Mumbo Jumbo?

Any input is grand.
Cheers

 

[Gareth Connor]

Can you elaborate further on "cable cooking"?

Other than the unpleasant overheating effect of too much current down too little conductior, I've never heard of it. Curious to find out (or work out) if it audiophile or audiophool.

Cheers,

 

[pucho812]

do some searches vato....

A description of a (typical) device to perform the ‘cable cooking’:

[the device] pushes a signal through your cables (interconnects, speaker cables, or AC cords) at hundreds of times the voltage and current levels than they're used to. The signal is a sweep tone, from the lowest lows to the highest highs (approximately 20 to 20kHz) that repeats and repeats, though not in your ear.

An explanation of effect:

Consider the metaphor of a stream bed. According to my geologist friend, John Curl, during the dry season, what with erosion and the usual squalls and mid-sized storms, the water has to go over and around the rocks and boulders strewn randomly along the streambed. White water would be a crude measure of the rate of collisions. During the rainy season, what with large storms and perhaps even hurricanes, the water comes with such force (miles per hour) and volume (gallons per hour) that the rocks and boulders are pushed to the edges (or bottom) of the streambed creating for the most highly energized water a path of least resistance.

Similarly, during routine use, even playing music loudly, the cables of the average system have randomly arranged crystals of metal in the path of the electrons causing collisions at a certain rate. The increased or decreased rate of collisions is inferred from the measurement of lost percentage in the ideal propagation velocity, expressed as percentages of the speed of light. During cooking, which is analogous to "flooding," the signal comes with such force (voltage) and volume (amperage) that the molecules are pushed into alignments that create a path of least resistance, from RCA plug IN to RCA plug OUT, causing collisions at a much reduced rate. I must plead ignorance of anyone's measuring the propagation velocity in an interconnect before and after cooking the cable. But, according to my ears, there is a difference, and the analogy works for me.

and from audioholic's.com

Cable Vendor Claim

"'Breaking in' a cable has everything to do with the insulation - not the wire itself. The insulation (or dielectric) will absorb energy from the conductor when a current is flowing (i.e. when music is playing). This energy-absorption causes the dielectric's molecules to re-arrange themselves from a random order into a uniform order. When the molecules have been rearranged, the dielectric will absorb less energy & consequently cause less distortion." Audioquest



Audioholics Response:

Thus their conclusion is the dielectric, not the wire causes distortion! Claims regarding insulation molecules "aligning" with a signal, skin effect, strand jumping, etc, are anecdotal at best. Let's not forget that an audio signal is AC, and effectively random from a physical perspective. Nothing can align to a random signal by being anything other than random - exactly the state they claim is "cured" by injecting a signal.



"Break In" is not a proven audible or measurable phenomenon. The perception of changes in sound quality with time is likely attributable to the classical placebo effect, i.e., a listener anticipating a possible audible difference is predisposed to hear one whether or not it exists. Note that Audioquest isn't the only exotic cable vendor that claims cables "Break In". This is actually quite a popular myth touted by many other exotic cable vendors and cable forum cult hobbyists alike.

I say they are selling snake oil. if your going to buy into that I got a bridge I own in Brooklyn that I would love to get off my hands for cheap. Could make a killing charging toll

 

[Gareth Connor]

Thanks pucho812.
Those are some interesting theories...... snake oil is a bit polite, though!

Cheers,

 

[Mundox]

:grin:

 

[Mundox]

Oh, by the way. I DO NOT support the idea. I am just curious to see if there's anybody here that has experienced the phenomenon.
There's a lot of people out there making truck loads of money of this.
Something needs to be explained, no?

 

[Gus]

http://en.wikipedia.org/wiki/Speed_of_electricity

drift

 

[Mundox]

Hi Gus,
Could you elaborate? Is that the explanation to the "wider stage" these cables can provide?

 

[pucho812]

Velocity of Propagation (VoP) or velocity factor is a parameter that characterizes the speed at which an electrical or radio signal or the sound signal passes through a medium. Expressed as a percentage, it is the ratio of a signal's transmission speed compared to the speed of light in vacuum or the speed of sound. Thus, transmission in a vacuum would have a VoP of 100. VoP equals the reciprocal of the square root of the dielectric constant of the material through which that signal passes.

This parameter is used for communication media such as data cables (e.g., Category 5 cable cables). Plenum data cable typically has a VoP ranging from 42 to 72 (42% to 72% of the speed of light) and riser cable around 70. A VoP of 70 would correspond to a speed of approximately 210,000,000 m/s or taking 4.76 ns to travel one meter. In some technologies, such as Ethernet/Fast Ethernet the maximum length is dependent on the propagation delay of the medium.

The drift velocity is the average velocity that a particle, such as an electron, attains due to an electric field. Since particles can accelerate arbitrarily close to the speed of light in the absence of other forces, the term "drift velocity" can only really apply to carriers in materials, and not to particles in a vacuum. Particles in solids, for example, actually collide or scatter with the crystal lattice (or phonons), which slows them down. Drift velocity is non-uniform as it involves electric field as an externally accelerating agent.

In a semiconductor, the two main carrier scattering mechanisms are ionized impurity scattering and lattice scattering.

where ρ is charge density in units C / cm3, and ʋavg is the average velocity of the carriers

where μ is the mobility of the carriers and E is the electric field (V/cm)


[edit] Derivation
To find an equation for drift velocity, one can begin with the very definition of current:


where
ΔQ is the small amount of charge that passes through an area in a small unit of time, Δt.
One can relate ΔQ to the motion of charged particles in a wire by:

ΔQ


where
n is the number of charge carriers per unit volume
A is the cross sectional area
Δx is a small length along the wire
q is the charge of the charge carriers
Now, normally particles move randomly, but under the influence of an electric field in the wire, the charge carriers gain an average velocity in a specific direction. This is what's called drift velocity, vd. And since Δx = vd Δt, we can plug it into the above equation.


Putting that back into the original equation and re-arranging to solve for the drift velocity:

 

[Mundox]

And in lay terms....?

:green:

 

[chrissugar]

Here is my 2 cent based on personal experience.

I can say that although I'm mostly involved in proaudio, I'm also interested in audiophile reproduction for my mastering setup. In my circle of friends, I have some audiophile types, and from time to time they come to me with some outrageous claims that smell like snake oil.
Even if some things sound totally against known science I have the bad habit to make some controlled tests, and most of the times (to my satisfaction) to debunk some of their claims.

I thought it will not cost me anything to do some tests that will prove or bust the myth related to "burning in" audio cables.
I manufactured some identical pairs of audio interconects from a new roll of quality Belden cable.
I left one pair of cables untouched, another pair "burned in" with high current DC (at one end PSU, at the other low ohm, high wattage resistor), and the third pair burned in with high current AC (at one end oscillator sweeping audio from 20Hz-20kHz and back, into power amp, at the other end of the cable a high wattage resistor). Left the two pairs to cook for days.
Then AB test from the same source with the virgin cable against the two cable pairs "burned in" with two different methods.

Conclusions?

DRUM ROLL

No hearable difference between any of the three cables.
So at least for me the whole cable burning myth is busted.

chrissugar

 

[Mendelt]

Isn't the whole "burning in" thing more about you getting used to your new audio system?

I think with criss's experiment we can rule out any effect on cables.

Will amplifiers and cd-players sound different when "burned in" ? Or is this only in extreme cases where elco's need to be reformed?

Maybe loudspeaker-cones will sound different after some hours of use. But I guess that when this really is audible that the difference after a few years of use (and collecting dust/ drying out/ glue and plastic disintergrating from sunlight) will be far more noticable

 

[NewYorkDave]

Elco as in Elco connectors? :?

The burn-in argument makes some amount of sense for speakers and vacuum tubes, for easily understood physical reasons, but beyond that I have a hard time buying it.

 

[pucho812]

Well we burn in new speakers at work but thats purely for physical reasons... But cables rubbish I say. Why elco's what makes them so special?

 

[hejsan]

pardon my ignorance, how do you burn in speakers?

thanks,
hejsan

 

[NewYorkDave]

Um, play music through 'em for a while, I guess. You sure as hell wouldn't want to do it with a continuous tone.

I wouldn't make a broad claim that using speakers for a while will necessary make them sound different. I just think it's feasible that it could since a speaker is an electromechanical device with moving parts.

 

[FLZapped]

No, No, yes.

 

[Guest]

[quote author="NewYorkDave"]Um, play music through 'em for a while, I guess. You sure as hell wouldn't want to do it with a continuous tone.
[/quote]
Now did somebody here do that and end up frying a load of gear?

 

[NewYorkDave]

Someone at my studio fried an EV Sentry with a 400-cycle tone at moderate volume. Guess who got to take it down off the wall and replace the burnt driver!

 

[pucho812]

we use pink noise Dave :thumb: Moderate volume

[quote author="hejsan"]pardon my ignorance, how do you burn in speakers?

thanks,
hejsan[/quote]
with a nice fire on my BBQ :razz: