IC Burn In Theory.

[Cafad]

A mechanism that could explain cable burn in. I’m not saying this is wrong or right I’m just saying that from what I have read on the subject and from what I know about plastics I believe this to be a plausible theory. I’m not sure I can give GFuNK the physics behind it but I’m willing to give it a shot.

I’m thinking about ICs with this but the same would apply to speaker cables. I have read somewhere (can’t remember where but I agree with it) that you don’t burn in metal, you burn in plastic. How can that happen you ask, well grab a drink and make yourself comfortable, this could take a fair amount of typing on my part.

An IC is a number of strands of copper (sometimes silver) wrapped in plastic and attached to connectors. They all have connectors, so I’m not interested in them, they all have a different number of copper strands of different thicknesses, I am interested in that but not until later for now I want to focus on the copper and the plastic.

Plastic, we are told, is a dielectric material and as such it can hold a charge for just a bit longer than we would like it to (referred to as its capacitance) and thus can affect the signal being sent along it. For burn in to be real that capacitance would have to change, yes? And it can, but to explain how I have to back peddle a little.

Plastic as we know it is not just a homogenous substance, or, to put it another way, just as oils aint oils, plastics aint plastics. When plastic is manufactured it starts out in a large vat that contains potential plastic (called monomers) and an organic solvent. When those monomers polymerize to form a solid plastic they join together in a very haphazard fashion and some of the solvent is trapped within the plastic. Over time this solvent will slowly evaporate leaving only the plastic.

That new car smell that people often talk about, that smell is the solvent evaporating from the plastic in the dash (and steering wheel, gear stick, etc) as the sun “burns in†your new cars dash the amount of solvent you can smell decreases with time until there is no more new car smell (OK, your car won’t sound different, but it is a fair analogy).

I believe this is what is happening to the plastic insulation of the IC as it is in use, the current flowing through the copper is changing the properties of the plastic in contact with the wire by evaporating some of the solvent present and so the effective capacitance of the plastic changes over time until there is so little of the solvent left that the properties of the plastic stabilize and the IC is considered burnt in.

Now, I said above that plastics aint plastics, this is very true. There are three main plastics that manufacturers use to insulate ICs, Teflon, Polyethylene and PVC and all have different “capacitanceâ€. Within polyethylene there are low, medium and high density polyethylene and each are manufactured in a slightly different way. They can also be applied in more than one way.

I have copied the following from Redgums website. I am not trying to pick on Redgum in any way, they are just one of the few companies that actually supply a decent amount of info in regards to their IC construction.

REDGUM’s RGAP 'Audio Pipeline' OFC Interconnect

The Design:

The REDGUM RGAP 'Audio Pipeline' OFC interconnect cables are

researched, developed, designed and manufactured in conjunction with some of the most

knowledgeable specialists in the industry. Designed to provide focus and sound staging, with

a strong sense of three-dimensionality, resolution and detail, take a listen and prepare to be

amazed!

The Construction:

The Centre (signal) conductor comprises of a bundle of 80 cores of

0.09mm Oxygen Free Copper conductor (OFC), lightly twisted, and encased in a special

foamed polyethylene insulating jacket. Both channels are then individually screened to a low

noise specification with a 12-section x 9-strand spc braided OFC sheath, designed to achieve

excellent RF rejection, very low capacitance and a low noise floor. The final outer covering is a

matte blue jacket with silver printing. The cable is terminated with gold-plated RCA

connectors, which feature an easy grip, ergonomically designed barrel, a Teflon insulator, and

matching matte blue jackets.

The Result:

The REDGUM RGAP 'Audio Pipeline' OFC interconnect accurately

extracts the maximum available information from a recording without ever erring towards

artifice or over-emphasis.

The Low capacitance results in less high frequency attenuation and distortion.

What you get is a cable capable of clarity and signal integrity even over very long distances.

Reproduction spans a broad and unencumbered frequency range with smooth, effortless and

seamless integration from very low to very high frequencies, without introducing any

unnatural peaks or troughs.

The Technicals: These are real-world measurements of a totally finished cable, including

the gold RCA plug terminations:

Length Resistance Inductance Capacitance

RGAP1 1m 0.08 ohms 0.18uH @200kHz 82.3pF @200kHz

RGAP05 0.5m 0.04 ohms 0.09uH @200kHz 55.7pF @200kHz

The short Technical version:

Is it a good cable? - Yes, it is!

So we have “foamed†polyethylene (don’t know what density, but the foamed bit is interesting, it seems that Redgum have a different way of applying the dielectric to the copper wire or maybe everyone else does it too and Redgum are the only ones who tell us this, who really knows) applied to 80 cores of 0.09mm copper wire.

OK, just had a thought while I was typing, if this pet theory of mine is a goer then it should take longer to burn in an IC that has more surface area of copper in contact with the dielectric, so an 80 strand IC should take longer to burn in than a 40 strand IC (assuming the same weight of copper), I wonder if anyone has ever tried.

Sorry, derailed my own train of thought there.

What all of this means, very broadly speaking, is that ICs are going to need different amounts of burn in depending on the number strands of metal, the plastic in use and the method of application of the plastic.

Then there are the cable companies that apply custom dielectric coatings, JW audio and anti cables are two which spring to mind. They apply a thin film of some proprietary substance and claim that it has a very low capacitance. Fair enough, let’s think about this for a minute. If the dielectric is very thin then there is far less in the way of solvent that could be trapped within it, there is also less of it present to “store†charge so the capacitance of the dielectric should be minimized and any change due to burn in should also be minimized. With this in mind the protection that the dielectric offers to the copper cable is probably also minimized so this may not be the best way to go.

If I can quote from another web site, Mike Lenehan has this to say about his Ribbontec IC.

If anything, we are even more excited about the results from our new Ribbontek interconnect. A specific width of copper foil receives the same initial preparation as the speaker wire, but is then treated with a coating to prevent oxidation, allowing us to use an air primary dielectric. By avoiding both the undesirable interactions of stranded cable and the skin effect problems of solid core wire, the Ribbontek interconnect offers smoothness, resolution and rhythmic drive that surpasses anything we’ve heard.

An “air primary dielectric†sounds like a good way to minimize any copper/plastic capacitance as well as any burn in effects. And he uses copper foil, I have a few ideas about that too but I’ll keep those for another time, another post.

So, assuming anyone is still with me after wading through all that, my theory is that the effect of burn in on ICs is due to the changing of the capacitance due to the evaporation of solvent from the dielectric material of the IC sheath.

Is anyone still awake out there?

[avalon]

Yes, still awake.

Interesting read - hope you have your flak jacket on tomorrow.....

[LogicprObe]

'An IC is a number of strands of copper (sometimes silver) wrapped in plastic and attached to connectors. '

What about the silicon?

Also, I have seen gold thread use to connect from the die to the leads.

Edited September 20, 2012 by LogicprObe

[Nigel]

Cafad,

Please explain how "burn-in" changes the dielectric. What temperature do youthink Burn-in reaches to make a change ?

Once more, what physical attribute of a cable (impedance, capacitance, inductance ,) changes with running a signal through it and

why has noone ever been able to measure the change? Yet some "experts" here swear they've heard a difference. Pure delusion.

[A J]

One of the cables I use that supposedly has a huge run-in time - like 500 hours, is sheathed in cotton ?

Not that I could notice a difference burn-in wise - maybe I just have cloth ears

[GFuNK]

So your theory should be easy to test... Measure the capacitance before and after.

[Cafad]

So your theory should be easy to test... Measure the capacitance before and after.

True, but I don't have anything to measure the capacitance with so I'll have to leave that to someone else. If my theory is on the money then we should be able to artificially burn in some ICs by just heating them up for a while. I don't have access to any fancy electrical test equipment but I do have access to a temperature controlled oven so I may see what I can do in that department.

Cafad,

Please explain how "burn-in" changes the dielectric. What temperature do youthink Burn-in reaches to make a change ?

Once more, what physical attribute of a cable (impedance, capacitance, inductance ,) changes with running a signal through it and

why has noone ever been able to measure the change? Yet some "experts" here swear they've heard a difference. Pure delusion.

In this case it wouldn't be temperature that is supplying the energy to evaporate the solvent it is the electrical current. And mate, I just told you my theory on what is happening so I have had a go at explaining how burn in changes the dielectric what more would you like me to say? To address the bold area of your post, I don't know but how about I google it and see what I can find.

Also, if you head over to DTV forums you will be able to find quite a long post (I went to a fair bit of trouble because I didn't believe that different metals, or cryo treatment, in ICs could be heard) by myself which compares several ICs and speaker cables and finds close to bugger all difference, and yet in the time between then and now I have changed my opinion on cables and believe that a significant difference is audible. So obviously I have heard something that changed my mind.

[Nigel]

1. "True, but I don't have anything to measure the capacitance ".

2."evaporate the solvent "

1. just wondering why you would start a thread "xxxx xxxxx Theory" (almost reference like), when perhaps you should have just asked questions.

2. ahahahahahahaa beauty !!!

[Krispy Audio]

Some people I've discussed this topic with have shared their own experiences. One interesting phenomenon I've heard more than once is that a new cable they've used started off sounding good, then after 100hrs or so has taken a turn for the worse, and then after 300hrs has peaked and shown its true capabilities.

[Cafad]

1. just wondering why you would start a thread "xxxx xxxxx Theory" (almost reference like), when perhaps you should have just asked questions.

2. ahahahahahahaa beauty !!!

1. I started a thread because GFuNK asked me to have a go and I agreed. And it is my theory, I would have called it a hypothesis but no one seems to use that word much anymore.

2. No, it isn't beautiful, it is just a possibility.

Some people I've discussed this topic with have shared their own experiences. One interesting phenomenon I've heard more than once is that a new cable they've used started off sounding good, then after 100hrs or so has taken a turn for the worse, and then after 300hrs has peaked and shown its true capabilities.

That just sounds beyond strange. Are there any cables it seems to occur on more than others?

[Krispy Audio]

It was just with one brand of cable, but common across power, interconnects and speaker cables.

[Cafad]

Would that brand have used a custom dielectric by any chance?

[Krispy Audio]

It's a brand that unfortunately doesn't go into that level of detail with their published specs.

[ArthurDent]

One of the cables I use that supposedly has a huge run-in time - like 500 hours, is sheathed in cotton ?

Not that I could notice a difference burn-in wise - maybe I just have cloth ears

It probably takes that long for the surface oxidation of the wire to kick in.

Cotton sheathed solid silver is pretty common, although silver oxide is not said to change the sonic signature, at least not in an unpleasant way.

And surprised no other comments about this. No plastic, no solvent.

[Cafad]

Thanks for the reminder KT, I had missed that. If so then that could certainly mess with my theory.

Is the cotton the only sheath used on those silver cables? They don't use an inner plastic sheath with an outer cotton covering?

[skippy124]

Re the testing of cables and components, I have access to equipment that can accurately measure most (if not all) of the parameters in question, and have previously offered to do before and after testing (and even offered to pay the postage both ways), but the offer is yet to be taken up by anyuone. I am very interested to see if there is any measurable change in any of the cable or component parameters due to a burn in process.

Cheers

John

[MWR]

How do people know how many hours something has been used?

I have no bloody idea, I mean if it's new I know if I've only used it for an hour or two

Also I just don't understand the theory regarding burn in unless what's being burnt in or run-in is mechanical, like a V8 for instance or a vibrator, do they require burn in? :lol:

Edited September 21, 2012 by MWR

[Krispy Audio]

How do people know how many hours something has been used?

Often it's an estimate, eg I usually spend 2 hours a night so can work it out. But others use hour meters. Especially if you're a valve user, it can be a handy device.

[MWR]

Often it's an estimate, eg I usually spend 2 hours a night so can work it out. But others use hour meters. Especially if you're a valve user, it can be a handy device.

Thanks Krispy

BTW do you need to burn in an hour meter?

[Krispy Audio]

Lol - actually I started thinking.....does a cable burn-in device perform better after it's burnt in?

[Lloyd]

Condoms are commonly made out of latex, polyurethane or polyisoprene and much research has been devoted to their burn in properties. Prevailing wisdom is that the longer the better, but that may be a myth.

The jury is still out on those made of lamb intestine.

[ehtcom]

So your theory should be easy to test... Measure the capacitance before and after.

I have an old pair of DIY cables. Teflon insulated.

Old 1m IC with ?? hours. Maybe 2000 to 3000 hours measure 235pf @ 15khz.

A brand new ones I just made measure 235pf @15khz.

Sounds the same too.

But my system probably isn't revealing enough.

Marantz SACD

300B PP monoblocks with passive attenuators. (100K input impedance)

Tannoy 12" Dual concentric.

Cheers, Earle.

[joz]

Condoms are commonly made out of latex, polyurethane or polyisoprene and much research has been devoted to their burn in properties. Prevailing wisdom is that the longer the better, but that may be a myth.

The jury is still out on those made of lamb intestine.

Apparently its better to remove the intestine for testing purposes, :eek:

[ArthurDent]

Is the cotton the only sheath used on those silver cables?

For the purists, yes.

They don't use an inner plastic sheath with an outer cotton covering?

But you can also use cotton sleeving this way.

[Cafad]

OK, in no particular order.

1. Does anyone know if cotton counts as a dielectric material? If it doesn't then there is obviously something else going on there.

2. If Skippy is willing I might just take him up on that measurement idea, I'll buy two new ICs burn in the crap out of one and then send him both and see what he can see.

3. Earle, is there anything else you can measure that might give us a hint, inductance, resistance, impedance anything at all?

Also, I recall someone saying something about a cable cooker a few months back. Does anyone remember who and would they be willing to "cook up" a particular cable for testing purposes?

And one for the marathon men, does a condom actually sound better after 100 hours of use? Also, how much current are you gennerally running through it during use? Just because you feel like you are plugged in to 240V doesn't mean you actually are!