What Exactly Does "Burn In" do for Electronics?


I understand the break in of an internal combustion engine and such, but was wondering what exactly "burn in" of electrical equipment benefits musicality, especially with solid state equipment? Tubes (valves) I can see where they work better with age, to a point, but not quite sure why usage would improve cables, for instance. Thanks in advance for your insight.
dfontalbert
you should visit Morrowaudio.com and read about cable burn in. Tons of great information, once read you will understand completely why this is required with all new equipment from cables to amplifiers.
Are you saying that you don't hear components break in or that you do and just don't know why?
It's a myth.
Search any topic on forum here and you'll see that there's overwhelming consensus on one's rig sounding best after about half an hour after turn on.

Cold, out of the box, not so good.

When brand spanking new, one can easily multiply that exponentially until, after awhile, half an hour is all you need.

Something has happened. Check out any spec on individual parts and you'll see optimum operating temperatures under which they are spec'd. That means they have to heat up some and not exceed those temps.

Again, cold out of the box, not so good. Warmed up, good. That should tell you something. Your pride and joy needs less time to sound good so what just happened?

I've heard the difference between brand new and broken in but others will tell you I'm crazy.

I assure you I'm not.

All the best,
Nonoise
I wouldn't waste too much time on explanations. These posts are from people who don't like audio and start arguments for fun.
I love audio and I still out no stock in burn in for electronics or cables. What it comes down to IMO is that with high end audio it's extremely easy to be self deluded. This is due to the simple fact that our ability to perceive sound with utter consistent precision is poor at best yet we tend believe we are highly capable of detecting tiny changes. The brain ear combination is highly sophisticated but as a scientific measuring device capable of isolating tiny differences from one listening session to the next it's unreliable to say the least. That is the crux of the audiophile dilemma.
Our ability to hear differences is no less accurate than our ability to see or smell or feel differences. We'd all be dead at an early age otherwise. Those of us who enjoy this hobby have refined our hearing to a level more than the average person. The same goes for our other senses and those who employ them more than others on a regular basis be it due to hobby or employment.

With these differences come impressions that we catalogue in our memories. All it takes is a quick listen to something to familiarize oneself and then swapping out something to ascertain a difference. It's not that big a deal. The same goes for break in. It's right there, not going anywhere and we listen and listen and lo and behold, those tizzy highs are now softened; that midrange just opened up some: the bass just got tighter and more extended.

My hearing didn't just throw in the towel and told my brain to accept it. My brain didn't just say what the heck, it's not getting any better so let's move on. Nor am I now able to hear something that was always there and only realize it a week after. None of that makes any sense.

Someone should see how long it takes for this topic to resurface. Must be a slow news day, or Costco had a big sale on dead horses.

All the best,
Nonoise
"I love audio and I still out no stock in burn in for electronics or cables. What it comes down to IMO is that with high end audio it's extremely easy to be self deluded."

I respect your opinion, but I would also suggest that just because you haven't been able to hear break in doesn't mean that others are deluded and what their hearing is not real. If you think about it, another issue with audio, is bridging what is fact and what is not real, based on personal experience. (I'm not trying to single you out here. We've all done it, myself included.)
Is an audiophiles aural memory infallible? Of course not. Therefore the differences you think you are hearing could easily not be real. Your measuring device (ears and brain) are not accurate enough or reliable enough to be trusted for such subtle differences. To think it is, is simply an inability to believe an unpleasant truth. Few people are willing to submit to a blind ABX test for 2 wildly different amplifiers. Would love to see someone volunteer for a blind ABX test on new vs broken in cables. The idea is absurd.

And by the way, I never said I didn't hear break in differences. I said that ears and brain alone are not to be trusted to determine such subtle differences. Especially when those differences are frequently pulled from listening sessions that have occurred days, weeks, or even moths apart.

Do I think high end audio offers better fidelity? Hell yes. I'm a dedicated audiophile. But to think I cannot be fooled into thinking I hear an improvement when none exists is delusional. It also explains the long line of foolish products marketed to audiophiles, often at great expense to the buyer.
I wish I could hear no difference because I would have saved thousands and would be happy with a boombox.
"And by the way, I never said I didn't hear break in differences."

It looks like you did.

"I love audio and I still out no stock in burn in for electronics or cables."

Assuming you meant to say put instead of out, I can't think of any other way it can be taken.

"Your measuring device (ears and brain) are not accurate enough or reliable enough to be trusted for such subtle differences. To think it is, is simply an inability to believe an unpleasant truth. Few people are willing to submit to a blind ABX test for 2 wildly different amplifiers. Would love to see someone volunteer for a blind ABX test on new vs broken in cables.

I've heard these arguments before. Again, I'm not trying to be mean, but can you back them up? When it comes to the measurement/science/objective type of people, they never produce anything. For all the talk of science and blind test's, they never have anything real to support their claims.

I'm willing to keep an open mind. If you can show me some real tests that were done and documented somewhere, I'll set the test up myself and see if I can get the same results. If it turns out that I'm wrong, I have no problem admitting it.
Zd,

Really, you want proof that audiophiles are easily fooled into believing in phantom sonic improvements? That's amusing. How about some proof that you can really hear the improvements from cable burn in? If any existed it would be the high end news of the century.

Let me ask you this, do you think there has ever been a fraudulent audiophile product making false claims of sonic improvements in the history of high end audio? I'll answer that for you, YES, of course. Next I'll ask you did that product have any true believers???? Again, I'll answer for you, of course it did. All fraudulent high end products have true believers that swear by the product for sonic improvements. Why? Simple, our ears can deceive us.

Let me conclude that a simple google search will reveal numerous ABX tests done in the past by reputable sources which consistently fail to produce any meaningful ability to distinguish differences in high end components. The onus is not on the person who rejects the claims of sonic improvements the onus is on the person making said claims. And believe me, if cable companies had any legitimate proof to offer it would be plastered everywhere. Does not exist.

Simply from a common sense perspective I can poke a large hole in the theory of burn in....why is it that burn in always Improves the sound quality. If we were to believe that the sonics of a component do indeed change during burn in, does it make sense that the change would 100% of the time be for the better??? Of course not, ridiculous. Yet never in decades of reading blogs and reviews have I heard someone report that a product sounded great out of the box but them after burn in it degraded. Nope, it's always better after burn in. That's one magical process I must say.
Scientists tested a frog. They cut off it's legs and they said "jump!"

The frog didn't jump.

Scientist therefore concluded that when frogs lose their legs, they become deaf.

It's not mine but I had to borrow it.

High end reviews are full of burn in for cables before they are reviewed. Google practically any cable review and you'll find it.
Claims can and will be made that are false and they will have their followers. Does it follow that all claims are so?
Can it be that 100% of cable burn in reviews being always for the better simply back up the claim that cables need burn in, thereby validating the claim?

All the best,
Nonoise
The change in the sound a new amplifier sends to the speakers as it gets more playing time is as real as it gets imo. Bass, for example, I've heard change substantially. The way bass loads a room can change and that change can be heard and felt several rooms away.

why is it that burn in always Improves the sound quality. If we were to believe that the sonics of a component do indeed change during burn in, does it make sense that the change would 100% of the time be for the better??? Of course not, ridiculous. 06-15-14: Jaxwired

Sound does not always improve with burn-in/break in. I've complained before that some power cords I've tried have lost bass weight and/or clarity as they had more playing time in my system. This was not a good thing in my book and a deal breaker. I can say too that the bass of some amplifiers I've tried tightened during break to the point that I did not care for it as much. Break in does not always bring about improvements in sound quality.
An ABX Blind Test
Here is but one example. Half got it right, half got it wrong, between highly rated Nordost Valhalla power cords and the cords that come in the box with the equipment.
I am not suggesting sonic differences do not exist between equipment and cables but, like Jaxwired, I believe it is easy in this hobby to perceive tiny sonic changes when the real reasons may be related to other psycho-acoustical influences.
Audio equipment testing
Wiki also provides some interesting discussion about objectivists and subjectivists.
"Is an audiophiles aural memory infallible? Of course not. Therefore the differences you think you are hearing could easily not be real"

If that's the case I guess you could turn it around and say the differences you think you don't hear could easily not be real...ha ha. Sorry.
Dragon I completely agree with you. My point is not whether or not the sonic differences are real my point is that we don't know for sure and that there is a possibility that we can be fooled or deceived by our ears. Since this is true, I like to consider more than just "did I hear a difference" when evaluating the worth of a product or concept like burn in. For one thing, I throw common sense into the mix. Certain products and concepts certainly are counter to common sense. For instance, cable risers, expensive feet under components with no moving parts, totem beaks, $1000 / ft cable, etc...
"06-16-14: Jaxwired
Dragon I completely agree with you. My point is not whether or not the sonic differences are real my point is that we don't know for sure and that there is a possibility that we can be fooled or deceived by our ears. Since this is true, I like to consider more than just "did I hear a difference" when evaluating the worth of a product or concept like burn in."

Fine. I agree.

" For one thing, I throw common sense into the mix. Certain products and concepts certainly are counter to common sense. For instance, cable risers, expensive feet under components with no moving parts, totem beaks, $1000 / ft cable, etc..."

Common sense has nothing to do with this. There are plenty of things in science that don't make sense to us, but are still correct. If you want to disagree about what kind of differences you can hear with different cables, fine. But just because something like an expensive cable or tweak doesn't make sense to you, that doesn't mean you are right just because you are basing your answers on common sense. So if you want to get to what the truth really is, I think the only way to get there is with some well conducted listening tests. I've done them before and if carefully planned, I don't see why you can't get accurate results.

The only thing I would add is that you can't just lump everything all together. All cables, all components break in, all tubes, ... that kind of thing. I take everything on a case by case basis. Results vary. Sometimes you can hear a big difference, and some things, small or none.
"My point is not whether or not the sonic differences are real my point is that we don't know for sure and that there is a possibility that we can be fooled or deceived by our ears."

No doubt. Especially when the differences are subtle, as is often the case.

I'd say always trust your own ears above all else, but also realize that nobody is infallible and we all have our limitations. Also that some may use this information for less than altruistic purposes, especially when there is money to be made.
To those who don't believe in, or who haven't heard a difference, with burn in:

- please sell me that brand new bad sounding $2500 phono cartridge with only 10 hours on it for 40% of what you paid for it

I can't even count the number of cables or electronic pieces or capacitors or other parts of all types that have continually changed with "burn in" use over time. The change isn't subtle from start to finish, though it can be subtle in degrees. 20-50 hours isn't usually enough time to get to the end of that change. More like 100-200 hours.

All I can think is ... if you can't hear it then maybe your system isn't as resolving as you think.
"06-16-14: Ptmconsulting
To those who don't believe in, or who haven't heard a difference, with burn in:

- please sell me that brand new bad sounding $2500 phono cartridge with only 10 hours on it for 40% of what you paid for it"

In all fairness to some of the other posters, I believe they were mainly talking about cable break in. Typically, a new phono cart breaks in more than any other component. To me, they sound broken when they are new. Cable break in is usually much more subtle (but it definitely happens). But they're not all the same. For example, I don't notice that much break in with my AQ cables. There is some, but they get to where they should be fairly quickly. I have some Cardas cables that take forever. 100's of hours.
"All I can think is ... if you can't hear it then maybe your system isn't as resolving as you think"

Maybe you're right but maybe your wrong and it's all in your head and you just happen to be a person that's easily duped? Could be, that's all I'm saying.
06-16-14: Zd542
I have some Cardas cables that take forever. 100's of hours.
ZD, as I'm sure you realize I have great respect for your experience and your sonic perceptions. But a question: How do you know that the improvement you are perceiving after 100's of hours is due to the cables, and not to something else in the system that has changed in the meantime? Or, for that matter, something that has changed in the AC power, or even the temperature or humidity of the room?

My question is prompted in particular by reports I have seen here from others about cables and power cords requiring seemingly absurd burn-in durations, e.g., 800 hours or more. Unless, and perhaps even if, that is done independently of operation of the system, such as with a cable cooker, or in a different system, or by using a power cord to power a refrigerator, etc., I don't see how any such changes can be distinguished from effects that may be occurring elsewhere in the system or its environment.

And even if the burn-in is done via one of those alternative methods, given that 800 hours represents more than a month of 24/7 operation, it would still seem very possible that some unrelated effect might occur in the system or its environment in that period, that could be responsible for the perceived change.

Best regards,
-- Al
06-16-14: Almarg

06-16-14: Zd542
I have some Cardas cables that take forever. 100's of hours.
ZD, as I'm sure you realize I have great respect for your experience and your sonic perceptions. But a question: How do you know that the improvement you are perceiving after 100's of hours is due to the cables, and not to something else in the system that has changed in the meantime? Or, for that matter, something that has changed in the AC power, or even the temperature or humidity of the room?

Best regards,
-- Al

Yes as Al has pointed out this this greatly overlooked.
Take any hybrid ESL speaker for instance, they are tuned for a certain sound by the factory.
The esl panel on a day when the humidity is 70%-100% can loose as much as -3db efficiency, making the balance sound bass heavy as the dynamic bass driver has not lost this -3db.
I have measured it on my new panels, dry day 5kv bias charge and on a humid day 3kv-4kv bias charge, I tend not to do any evaluations or serious listening on days when the humidity is above 70%. Or if I have to, I can with some trouble turn down the gain of the bass electronics by the appropriate amount so all is balanced again.

Cheers George
From a teleological point of view, it makes great sense for our auditory system to be good at classifying sounds while ignoring minor differences. You needed to know if a predator or something to eat is is nearby. It wouldn't have served our survival well if we attended to small differences in sound. Audiophilia is but a recent pin point on the evolutionary scale.

My early research was concerned with testing theories of binaural hearing, so I've done lots of forced-choice listening under lab conditions. We can tricked into attending to small details, but we aren't all that consistent in doing so, and variability among listeners usually swamps those differences.

Count me with the skeptics, although I'd swear I can hear break in of disc players.

db
Makes sense.

I do think I hear a difference with some new power cords, but so subtle its hard to be certain.

I definitely hear differences with different analog ICs. DIgital ones, less so.

And rolling tubes in my tube DAC....absolutely no doubt.

I think burn in is a real consideration for mechanical devices, like speakers. ALso for some electronic components, like caps and probably transistors.

I suspect there is "burn-in" aspect with wires as well, but to a lesser extent that might matter less practically in most cases.

It's shades of grey, not black/white. No two things are exactly the same nor do they remain 100% constant over time, but practical effect may still be insignificant or even nonexistent in many cases.

Almarg is correct to point out that there can be many factors at play to account for perceived differences over time, and isolating each is difficult in practice, especially outside of a highly controlled envrionment, like a laboratory. When the differences are subtle on teh grand scale of things, one must always wonder and not be too quick to associate cause and effect.
I guess it is the term "burn-in" that piqued my interest - I inferred a physical change, and there very well may be - whether magnetism, heat, or some "alchematic" result, lol. Anyway, it is very interesting, and I wonder if the those changes have ever been measured? I assume possibly resistance, and other qualities surely have, over time. My equipment has most always been pre-owned, so I have not really experienced the change. I appreciate the discussion and I definitely didn't start this thread to instigate argument.
06-17-14: Mapman
Makes sense.

I do think I hear a difference with some new power cords, but so subtle its hard to be certain.

These can be a bit different sound, as they have earth, neutral and live. Some shifty mains cable makers swap the neutral and live around, while all still works, they are attached then different within the primary winding of the equipment's mains transformer, as it has an outer feed and inner feed.

And this even though it's AC can this sound different, making the user think it's the actual mains cable itself causing the difference.

You can prove this to yourself with some cdp's that only have a two wire main cable with a reversable 2 pin mains plug on the back of them, each way sounds different to the other even though it's the same cable and plug.

Cheers George
"06-16-14: Almarg

06-16-14: Zd542
I have some Cardas cables that take forever. 100's of hours.

ZD, as I'm sure you realize I have great respect for your experience and your sonic perceptions. But a question: How do you know that the improvement you are perceiving after 100's of hours is due to the cables, and not to something else in the system that has changed in the meantime? Or, for that matter, something that has changed in the AC power, or even the temperature or humidity of the room?"

As far as knowing for certain that the sound I get with Cardas cables before and after break in, is actually due to break in, is that I can't know for certain. That said, its the only explanation that makes sense; at least to me. My system's usually don't change too much, so I don't have to deal with trying to listen around other changes in equipment (For the most part. I'm sure that there were some cases where I changed equipment during the burn in process.). The main thing that leads me to believe the results I get are due to break in is consistency. With my Cardas cables (Golden Reference), the cables have a sound when they are new, and a different sound when they are broken in. But its always the same. Also, they all take about the same time to notice the change. I wouldn't say 800 hours, though. Somewhere between 300-400. That's with a CD player on repeat playing white noise, 24 hours a day.

Could the break in really be due to a change in the AC? Its possible, but I don't think its very likely. I've done multiple pairs of the exact same cable, all with the same results. If the AC was to blame, you could just as easily get the sound that is the end result (after burn in) first, and then burn in to what the cables sound like originally, when new. Or, there could just be no change at all. Even if you've had issues with sound changing due to AC, it doesn't mean it has to be a factor every time. So, that's why I rule out AC. The results seem to be too consistent.

Temperature and humidity? Al, you have me on that one. I never checked. lol. I have no idea how much of a factor that will be. Some of my equipment is in FL, and the rest in NY. Humidity and temp in FL is fairly consistent. In NY it is not.

Just to sum up, break isn't something that any audiophile should be worried about. I feel that time is much better spent focusing on other topics. In the end, everyone gets the same results. If break in does happen, it doesn't matter if you believe in it or not. It will take care of itself all on its own, with a little time. And if it doesn't happen, or you can't hear it for some reason, you still have the same end result.
"All I can think is ... if you can't hear it then maybe your system isn't as resolving as you think"

Maybe you're right but maybe your wrong and it's all in your head and you just happen to be a person that's easily duped? Could be, that's all I'm saying.
**************************************
Jax ... in some cases I might agree with you, but in others the change is so profound that there is no way to mistake the change. Dull, uninvolving, 1 dimensional, no dynamics, no top or bottom end slam ... changes to ... open, airy, extended, 3 dimensional, exciting, slamming sound that you just can't stop yourself from getting up and dancing musical enjoyment.

It doesn't matter that it took 2 weeks to get there, you can easily hear it.
ZD, thanks for the thorough response. I will say that when it comes to reports of phenomena that are difficult or impossible to explain, I would have a good deal more confidence in yours than in those of many others, who often seem to not consider the possibility that the perceived change may be caused by something other than what is being assessed.

George, thanks as well for the inputs in your two posts. All I can say is "wow," to both of them.

Best regards,
-- Al
I tend to agree with Jaxwired. Humans are extremely fallible regarding subtle sensory perceptions and despite what some people allege, high end audio is about subtle differences. This doesn't mean cable break-in doesn't occur, but that we should take these observations with a grain of salt.
Al, Zd... and George ... I realize that the more recent posts are speaking to burn in of cables and power cords.

What are your views about electronic gear? FWIW, ARC maintains that its gear requires a considerable amount of break-in.

I'm not sure what is happening inside the box, but there must be something to it ... at least with respect to electronic gear. Maybe the caps are settling in?

There must be a lot of material science going on here that is way over my head. As far as cables and power cords are concerned, is it possible that running current through the cables and cords in some ways affects the metallic crystalline structure?? That is a serious question?

Btw, maybe not so crazy. I understand that low temp cryo "cooking" of metallic parts like gun barrels, engine parts and so forth changes the crystalline structure. The result is stronger and longer lasting parts, so the cryo proponents maintain.

06-18-14: Bifwynne

Btw, maybe not so crazy. I understand that low temp cryo "cooking" of metallic parts like gun barrels, engine parts and so forth changes the crystalline structure. The result is stronger and longer lasting parts, so the cryo proponents maintain.

I think cryo'ing has been overdone in audio, it's fine to do material of one substance like a gun barrel.
But when people start doing tubes, this is just not on.
As the rates of expansion and contraction of unlike materials like metal tube pins that are an air tight seal with the plastic base and the glass that is a seal with it, just think of what happens to the vacuum in the tube when this is cryo'ed.
Then lead solder on plated metal interconnects with silver or copper wire three different materials all contracting at different rates, solder is bound to get cracks in it.

Cheers George
George, I can certainly understand your concern and your analysis seems like it might hold water. The problem with your analysis is that in reality tubes are cryo'd everyday in cryo labs around the country without experiencing any problems.
"The problem with your analysis is that in reality tubes are cryo'd everyday in cryo labs around the country without experiencing any problems. "

Seldom does anything happen without some problems, except in a perfect world, so something a bit more concrete than saying it is so would be useful. Saying something is so does not make it true. Especially when there is money to be made.

Prescription drugs are marketed to us continuously these days. You get a brief summary of the drugs benefits and then you get the many possible side-effects.

At least companies that push drugs are regulated to the extent that they have to disclose pros and cons fully. No such luck with high end audio. THe stakes are just not high enough to regulate anything so its pretty much the wild wild west where anybody can claim anything at anytime with no substantiation and get away with it perhaps.
06-18-14: Bifwynne
What are your views about electronic gear? FWIW, ARC maintains that its gear requires a considerable amount of break-in.
FWIW, my instinct would be to consider their recommendations as credible, certainly for their own products. Tubes, capacitors, and (I suspect) transformers and transistors, and perhaps even resistors, can be expected to change their characteristics to an audibly significant degree during some period of burn-in. To a greater or lesser extent depending on the specific circuit design, the specific parts that are used, and on how much testing and burn-in is done at the factory.
There must be a lot of material science going on here that is way over my head. As far as cables and power cords are concerned, is it possible that running current through the cables and cords in some ways affects the metallic crystalline structure?? That is a serious question?
My feeling is that it's over everyone's head, in the sense that all kinds of explanations can be hypothesized, one of them being dielectric absorption effects which are commonly cited, but given the difficulty or impossibility of establishing (either analytically or empirically) that a given hypothesized explanation is great enough in degree to have a reasonable chance of being audibly significant, any such hypothesis is unlikely to be either provable or disprovable. Which is one reason why:
06-19-14: Mapman
... its pretty much the wild wild west where anybody can claim anything at anytime with no substantiation and get away with it perhaps.
+1

Best regards,
-- Al
Mapman wrote,

"... its pretty much the wild wild west where anybody can claim anything at anytime with no substantiation and get away with it perhaps."

The difference being I have experience in cryoing audio items, 15 years of experience. Whereas you have, uh, none. So I guess it's actually YOU. who are claiming anything at any time with no substance. Duh!

Al gets a big -1

:-)
"The difference being I have experience in cryoing audio items, 15 years of experience. "

Geoff, saying something doesn't make it true. It applies to everyone.

What I see from you is all words, doubletalk as needed, and hoaky products with only words to justify them.

That doesn't make that true either.....but I would play the odds....
Mapman, not really sure what you hope to achieve in this discussion other than to reiterate common naysayer qualms and angst related to unconventional audio activities. Yes, it is a democratic hobby, so even those folks who have stopped trying to improve their sound a long time ago can express contempt or skepticism or whatever as it's a free country. If you wish to be recognized as the leader of the pseudo skeptics that's fine with.
Mapman, not really sure what you hope to achieve in this discussion other than to reiterate common naysayer qualms and angst related to unconventional audio activities. Yes, it is a democratic hobby, so even those folks who have stopped trying to improve their sound a long time ago can express contempt or skepticism or whatever as it's a free country. If you wish to be recognized as the leader of the pseudo skeptics that's fine with me.
"Prescription drugs are marketed to us continuously these days. You get a brief summary of the drugs benefits and then you get the many possible side-effects.

At least companies that push drugs are regulated to the extent that they have to disclose pros and cons fully. No such luck with high end audio. THe stakes are just not high enough to regulate anything so its pretty much the wild wild west where anybody can claim anything at anytime with no substantiation and get away with it perhaps."

That's a good point, but I do get a good laugh sometimes when I read the list of side effects. They say just about anything that could ever possibly happen; known and unknown. Of course, its done for CYA purposes. This drug: may make you hot, may make you cold, may give you a headache, may make you head numb, may make you happy, may make you sad.... the list goes on. What I really like about claims audio companies make, is that they're always positive. lol. No way out cables are going to give you headaches. Not even the silver ones.

"THe stakes are just not high enough to regulate anything so its pretty much the wild wild west where anybody can claim anything at anytime with no substantiation and get away with it perhaps."

With regards to that statement, in particular, it may be true in some cases, I don't think the overall situation is quite that bad. Up till this point, I don't think anyone has mentioned patents. Most audio companies do get patents on their work. I'm not a legal expert, but I'm pretty sure you can't just get a patent on anything you want. There has to be some qualifications. The patent has to be on something unique and not conflict with any other patents. Also, I think that you need to show that whatever you are getting a patent on has to do what you say it will. Even is its only on paper and in the design stages.

Just to be clear, I'm not saying that patents are guarantee's that you will get a certain level of performance from your audio gear. They may, however, give some credibility to a design and maybe even take it out of the wild west category. Something to consider, that's all.
With the cost of patents these days running around $10,000 bucks a pop that's a lot of spinach to get some supposed credibility. Besides, one stipulation for a patent is you actually have to describe in excrutiatingly detail how the things works. Furthermore, if someone in some godforsaken part of the world is clever enough to knock it off there's not a helluva lot you can do about it. Not to mention curious little audiophiles with too much time on their hands. Lol
I don't know what you guys are talkin about. Burn 'out' is more like it. As soon as I get a component back from rebuild, it's awesome for the first little while and then loses that pinnacle of peak performance, settling down to long term stability. Sheesh. WAKE UP!
Obviously, like most industries with a long history,there are a lot of quality companies and people in high end audio.

Then there are the pure charlatans and everything in between.

It is what it is, not that much different really than most things.
"Burn in" believers imply that something will change for the better after a period of time.
The only way this can happen is if the characteristics of the components change.
All good equipment is measured, tested, calibrated and designed to perform it's best before it leaves the factory.

If any of the above characteristics change after this with "burn in". Then this equipment will not test the same, be in calibration, or measure the way the designer wanted it to remain when it left the factory. And could only sound worse after "burn in".

Ok lets say things do change after "burn in", how does any designer compensate for this, in his calibrations, measurements, tests and design????

The only thing in audio I know of that can change "sound" for better or worse, are mechanical things like speaker suspension systems

Cheers George
"Ok lets say things do change after "burn in", how does any designer compensate for this, in his calibrations, measurements, tests and design????"

They compensate for this by breaking the prototypes in before they listen and measure. For example, a designer may want to try several different capacitors when building an amp to see which one sounds the best. If they want to try 5 different options, they break the amp in 5 different times. They don't do any serious listening or measurements until they break the amp in first. This is the way they all do it. I don't think you could find one company that doesn't break their equipment like this. You don't have to take my word for it, either. Call some manufactures and ask them.

I think the compensation issue is apples and oranges. Break in at the manufacturer is about ensuring it stays in spec. Changing out parts for different effect has nothing to do with so-called burn in. The same issue would apply.
I love it when people speak in absolutes. It's like when people demand. Limited life experiences are one source of this behavior or in this case, limited listening experiences.

Having a closed mindset implies one is not open to learning (hearing) something. Speaking in absolutes (or stating) demands no other course but the one proffered. It's akin to generalizing, which I do my best to avoid. It requires constant discipline.

All the best,
Nonoise
Generalizations are the source of all wisdom.