Equipment Break-in: Fact or Fiction

I agree with Redkiwi 100%. I too am a staunch believer of burn in for all components. I have heard it with my own ears and I feel I have very good hearing. The human ear is far more accurate than any and all electronic devices designed to hear distortions,etc.Some people hear things differently and that is normal.That is why we are all unique.But any true-blooded audiophile, with a trained ear should be able to hear the break in of a new power cord,speaker cable or interconnect.

The reason why I leap into these discussions about burn in is that I believe that failing to allow for burn in is the cause of so many bad mistakes by audiophiles. The problem is if we cannot even agree that burn in exists then we will not agree that even burnt in components take a while to settle after shipping, and then it becomes pretty difficult to warn newer audiophiles about the perils of hasty auditioning.

I have no doubt that fears, Marakanetz, that marketers and salespeople exploit the burn in story to pull the wool over peoples' eyes, have some foundation in fact. What I am more concerned about is that without an appreciation that burn in is a factor, then many will come to quite erroneous conclusions about components and cables that they try.

Take for example, the comment I have heard that the Plinius SA102 lacks PRAT. One that has been used for less tha around four months sounds exactly so - soft and sluggish. The fact that it sounds so is utterly obvious in any competent system. But equally, a burned in SA102 has PRAT in spades, and that is again quite obvious.

So if you suspend your disbelief for a moment, you may understand why I believe that nay-saying on burn in will cause newbies to be quite confused and waste a lot of time if they rely on an overnight trial of equipment before buying.

Gents and Ladies,
This is the most interesting post here IMO ever that occured for the whole Audiogon existance and I do appreciate these controversal thoughts that came up here.

Man of science tend to deny or assume but the final result should be the number and/or equation.
Electronics do involve influence of chemistry and thermo-dynamics and even maybe in our discussed burn-in proccess in audio freequencies.

I however still hold my position towards believing that burn-in is more of a marketing and psychological issue rather than physical process, but there could be different long-term factors that I have no knowlege how to define or calculate them; therefore I only assume that influence of thermal adoptation along with other values of a chemical and physical proccesses can be neglected compared to the electrical.

Nowdays, as I believe I described my understadning of burn-in proccess as function depending on time by simple 7th grade physics formula by simply dividing the signal path over the speed of light for the peak of the equipment performance.

Also I greatly appreciate everyone along with author for bringing up different thoughts. Let them ALL be honored and not to be attacked whether it's from scientists or ordinary people.

Redkiwi,

Good to meet you also... Sorry I really thought i was
being attacked.

Im guessing most of the people in this forum are pretty smart (yes even if their not engineers) and alot of them are probably perfectionists also. There seems to be a certain type that gets drawn into HI-FI.

One point i want to make is alot of the engineering people
i know dont have the faintest idea the difference between
a good audio component and a bad one. One of my buddies
is a brilliant engineer and he thinks the stock CD player in his car is just fantastic. I almost puked when i drove somewhere with him and he turned it up. My dad has been
in electronics since he was 16... thinks 50 bucks is too
much for a speaker its unbelievable. You should see the look
on his face everytime he comes over there's always new stuff.. He just shakes his head and gives me that your crazy
look. So what im trying to say is even being a good or even brilliant EE doesnt qualify anyone as being an audio expert
automatically...I do understand that.

There are plenty of people here that i want to learn from.
With years and years of experience. I have years with musicical instuments and electronics but i dont have years of HI-FI knowledge. And that is what i love now.
So whenever i think i can make a good point i will throw
it out there but at the same time im listening more than
anyone for other points.

Bob just read your post I understand 100% and i agree.
Thats why im here.

To learn..

Best regards

Alright then gentlemen; I agree let's all bury the hatchet & I retract any controversial inflamatory remarks.
I have heard these audiophile theories & have laughed at probably 95% of them too - but when I hear the evidence for myself then I have to believe that there's a lot more to this than the textbook theories ever taught me in engineering school. That's right; I'm one of *those* myself. Not to be haughty about it though; long ago I too refused to believe I'd ever accept any of this nonsense, but an open mind + experience has admittedly taught me differently & made my rig sound so much the better for it. And *that* my friends is the bottom line IMO.

That's totally cool Spluta, and pleased to make your acquaintance. There is no bias against engineers that I can see, just a bias against those with closed minds that always assume posts here that don't match their knowledge must be the ravings of deluded fools.

I am surrounded by hundreds of engineers at work and I can see why the issues arise. While there are fantastically clever and interesting engineers in the team, most are worker-bees by comparison (not their fault, just dipped out in the gene pool) who are trained to work within engineering rules that have been established by others - nothing wrong with this, just good practise. But the years of not questioning their boundaries seem to me to take some of them them far from being experimental scientists and they get very rigid in their thinking - only some.

Now I am not saying you are like this. When I read your posts I can see that is not so. But we do get one or two here who like to pounce on someone who is honestly expressing their experiences and beliefs and demand scientific proof or a retraction and a thousand hail Marys. Their justification for taking a 'holier than thou' attitude is often a statement about how they are engineers and our poor dumb fools should just listen up - hence the occasional cringe factor.

Now being mainly an economist, I can understand the sentiment. Boy do you hear some really dumb theories from 'bush' economists. But it is simply rude, arrogant and self-defeating to say - your opinion does not count, because I am the economist and you are not, and I say you are wrong.

That's totally cool Spluta, and pleased to make your acquaintance. There is no bias against engineers that I can see, just a bias against those with closed minds that always assume posts here that don't match their knowledge must be the ravings of deluded fools.

I am surrounded by hundreds of engineers at work and I can see why the issues arise. While there are fantastically clever and interesting engineers in the team, most are worker-bees by comparison (not their fault, just dipped out in the gene pool) who are trained to work within engineering rules that have been established by others - nothing wrong with this, just good practise. But the years of not questioning their boundaries seem to me to take them far from being experimental scientists and they get evry rigid in their thinking. Now I am not saying you are like this. When I read your posts I can that is unlikely. But we do get one or two here who like to pounce on someone who is honestly expressing their experiences and beliefs and demand scientific proof or a retraction and a thousand hail Marys.

REDKIWI,

This is what i missinterpreted(see paragraph below)

The alternative explanation is that some people have brains that immediately decode the distortions in a new system and others are handicapped in this ability and take 300 hours. Being biased I don't like the thought of being handicapped in the brain department, so you can guess which one I prefer.
- The 300 hours burn in is the most persuasive point for me. How come the burn in appears to occur whether we listen to it while it is burning in or not. The alternative explanation is... we are deluded by our prevailing belief in burn in, or I guess we are just lying to prove our point. I can imagine how you could make that assumption. But you can imagine why I don't.

/

As far as i know i am the only retarded idiot (on this thread) that claimed to have heard differences till 300hrs. And was lying to make his case.
I APOLOGIZE...I misread that 100%... I read that as coming
right at me.

I certainly dont mean to crash the party. I am here because i love music/equipment not TDR'S or scopes. I had no idea you guys are so biased against Engineers. Just remember we are the ones who design this overpriced gear. Your welcome.

Again I apologize.

I am gonna switch to de-caff tommorow...

Thanks Paul - I was definitely reaching with that 'freak' comment, I forgot there were so many of you good guy freaks out there, till I came back to Audiogon, even if you cannot hear the sound change with new components. I secretly envy you - I hate the burn in period.

Now you've ticked me off, Redkiwi. How can you say it's insulting to call someone a freak? I'm still a freak and proud of it.

I found your observation about those who believe speakers make the most difference also being people who disbelieve in the burn in phenomonenon interesting. Probably accurate. I certainly think speakers make the most difference, and I have never noticed any change over time in any electronic component. Tubes, phono cartridges, speakers, sure.

In reply to Bundy's original question above, I agree. I've always thought the retailer's advice that a customer has to give a new component a chance to burn in is the best evidence that electronic things sound different from each other. Otherwise, there would be no reason to have the customer get used to the new sound.

Nice to see you back Red.

Now I'm really confused. I just skim-read Splutas posts and didn't find anything obvious that I even disagreed with let alone contradicted in my post. You are going to have to help me here Spluta.

Spluta, you clearly take yourself very seriously - you mistake me for someone that was responding to your post - I was not.

I am at a loss to know which of my words were directed at you, because I cannot remember reading your post(s). Nothing you wrote in any of your posts was in my head when I wrote my post.

Frankly you flatter yourself when you say I called you a liar. I can assure you I called you nothing and did not give the idea a second's thought. All I can assume is that you found my post contradicted yours and then for some reason believed I meant to make a personal attack on you. What I did was try to describe my beliefs and why I believe them. Is that OK with you? If your reading of my post drew you to the conclusion I was belittling your opinion then I apologise for my clumsiness, but there was no intent.

Without going back and reading your earlier posts I expect it was my term 'measurement freaks' that did it? If it was not that then I am at a loss to understand what has offended you and you will have to explain. Perhaps I should go and read your posts and see if I can work it out. If it was the 'f' word, then I have to admit the word 'freak' is insulting so withdraw it. How about 'measurement zealot'? Perhaps still too negative. 'Measurement guys' just lacks a certain ring to it, if you know what I mean.

On the subject of measurements, as Bob says, the intention of most of us in this hobby is to enjoy listening with our ears. If measurement helps identify which equipment will be better or worse for that purpose, then it has value. I think that shelf life past several years ago, except to assist equipment designers. So far I am unconvinced of the connection between audible abberations and measurements, with most modern gear having a level of competence that goes well beyond the distinctions that measurement appears able to identify.

What I find annoying is the fact that 'measurement guys' repeatedly insist on spoiling the party here by interrupting the sharing of experiences and opinions, by entering with a "I'm an electrical engineer (pause for oohs and aahs), and my text books don't tell me about what you just said so it must be wrong." And no, Spluta, relax - this is not directed at you. I have no idea whether you ever said anything of the kind. It is directed generally at the several who take that position.

When somebody calls me a liar i take it seriously.
Wouldent you Bob? Did you read what he wrote? It
was totally uncalled for.

Is that a new one? Never heard that before.

One interconnect cable pair that I tried actually got worse with usage if that makes you naysayers feel any better? Or do you not believe that either since I didn't have my trusty distortion analyzer telling me what I'm hearing? Jeez Louise - we play music to LISTEN to it, not to MEASURE it with instrumentation for cryin' out loud.
Spl's insulting demeanor contributes nothing useful here & only serves to negate any possible credibility that may have been initially perceived.
Measure THIS! ;-)

Redkiwi,

First of all I dont appreciate your words directed
at me. I was simply describing MY experience which
YOU had nothing to do with. So you wouldent really
have ANY IDEA about it would you? You can guess all
you want... you will be running in circles the rest
of your life... It sounds like youve been at it awhile.

I was trying to throw some REAL possiblilities out there
that can be MEASURED. That is why we have devices to
measure so we dont have to rely on Kiwifruits's brilliant
mind distorting deductions.

I didnt come to this forum to have my integrity and
thoughts questioned by someone who doesnt know me or
my equipment so i would APPRECIATE you not doing that.
I really dont think anyone here would appreciate that.

Oh and by the way even measurement devices drift and have
to be re-calibrated.

I will try and answer it Ben - not because I know the answer, but because my experience of break in and different people's opinions on it seem to converge on a particular conclusion, in my mind.

First, I believe that both component and psychological break-in occur. But I cannot prove either.

I have experienced the phenomena of a CD sounding odd on first listen and then sounding more 'right' after a few more listens. I believe that this is not due to anything else changing than my brain getting accustomed to decoding the particular distortions on that CD. I believe that this is essentially what the brain does when it processes sound information it receives from the ear. It tries to correlate it with sounds it is more familiar with and then decides to 'hear' the sound in a way that the brain has determined is the sound of the true event.

This is a little like the way when you record music you have to keep the sound of the recording acoustic low in the mix. I believe the brain finds it easy to keep the sound of reflections out of the way of the sound of the source of that sound when it is in the same acoustic environment, but when listening in one environment, to an event recorded in another, the reflections in the recorded acoustic are difficult to put aside at the same time as putting aside the acoustics in the current environment. This is why you hear lots of sound reflection when you listen to a simple recording of your voice.

So when I hear a new CD - I am not saying the issue is reflections, that was just an analogy - my brain takes a while to get used to hearing past the distortions that are unique to that particular disc.

I have no doubt that this happens when we hear a new stereo system or just a component change to a new stereo system.

But I do not accept that this phenomena explains the changes I hear while a component breaks in. The following observations are what I base this on.

- I don't hear CDs change their sound from thin brittle and bassless, then thick and murky, then hard and edgy, suddenly soft and mushy and then finally sharpen up to sound about right, in the way that some new components do. The alternative explanation is that the distortions of a component are manifold and my brain learns to decode them one at a time and so the sound moves around each time it deals to a particular type of distortion. Maybe.
- I take much less time to decode the sound of a friend's system than I do to decode the sound of a new system I put together. The alternative explanation is that I am either less critical of my friend's system than when my money and future musical enjoyment is at stake, or I am just atrocious at putting systems together such that my brain needs way longer to deal with it. Hmm, unlikly Ben, and fairly conclusive evidence for component break in - in my mind.
- Whereas when taking a CD out of the system for a month or two my brain has no trouble finding it to sound like the last time I heard it, taking a cable out of the system and curling it up in the cupboard for a month results in me hearing a break-in occurring for anything between two days and two weeks. The alternative explanation is that the distortions of a cable are more complex for my brain to decode than the distortions of a CD. The measurement freaks will have trouble with that one.
- I also respect the validity of other peoples' conclusions from their experiences, not just my own. I observe that many who claim that there is no component break in also state they hear little or no change during break in, and that many who claim that component break in exists, also state that they hear significant differences during break in. This is explained if you accept some people are more irritated by the distortions that go away as a component breaks in. The alternative explanation is that some people have brains that immediately decode the distortions in a new system and others are handicapped in this ability and take 300 hours. Being biased I don't like the thought of being handicapped in the brain department, so you can guess which one I prefer.
- The 300 hours burn in is the most persuasive point for me. How come the burn in appears to occur whether we listen to it while it is burning in or not. The alternative explanation is... we are deluded by our prevailing belief in burn in, or I guess we are just lying to prove our point. I can imagine how you could make that assumption. But you can imagine why I don't.

The interesting thing is there seems to be a correlation between those that deny burn in and those that believe the component that makes the most difference in a stereo system is the speakers. In fact I find this very interesting. I suspect we listen for different things, have different musical values or simply are irritated by different distortions. You see I find most speakers that survive commercially today in the high end are capable of sounding musical. Whereas I cannot say that of amplifiers - the very opposite of what the measurements would lead you to believe. Therefore I strongly suspect that there are distortions that irritate me, and many like me, that do not pop up as significant in conventional measurement (which pro-rates distortion issues rather liberally), are endemic in electronics and less measurable than speaker mechanical distortions, and that reduce dramatically during burn in.

Finally, I have experienced components sounding more pleasing in tonal characteristics during burn in than after burn in - but there is nevertheless something else wrong during burn in. Perhaps it is a form of phase distortion that upsets my brain (and others like me).

Ben, I'm sorry, but I just don't know the answer to that question. I'm sure there is some reason, but I don't know it. If I were to venture some kind of unfounded theory, I might say that there is some kind of "memory" in the structure of a wire, or part, that retains certain characteristics for a time. And maybe, it takes a little while to get this "memory" to settle in. And maybe once it is settled in, it takes a while for it to go away, which would explain why break-in needs re-doing after a long dormant period. And maybe once the wire or part is broken-in, it retains the "memory" of what it is like in its "warmed-up" state. Who knows? It is not impossible for a device to have a "memory", because as we know, a NiCd battery is well known to have a "memory" for charge and discharge levels. Plastics and rubber have "memories" for shape. Who's to say that a wire or part may not have a "memory" for something like this? When you first get the piece, maybe it has the "memory" of being manufactured, and no "memory" of conducting electrons. Maybe it takes a while for the electron conducting "memory" to build up. Once it does, maybe it stays in that good conducting state for a certain period of time. Maybe it affects the condition of the bonds on the valency electron shell, which allows better "jump" during flow, and the partially energized state may exist for a period of time. Maybe maybe maybe. Just thoughts.

Marakanetz..

Er is the dielectric constant of a planar material.

It is how fast (propagation delay) the electromagnetic
fields can pass thru. It is different for all materials
for instance signals on a PCB inner layers Er 2.8 will always travel slower than signals on the outer layers Er 2.8-4.5 because air allows electromagnetic fields to pass
easier. What Im saying is moisture also plays a part and
could effect the Er so until the moisture is gone fields
wont pass as easy. I am not saying the fields will change
the structural make up of the material. Only its ability
to allow electromagnetic fields to pass.

Hope that answers your question and by the way i like
di-poles much better easier to deal with...

Twl-I respect your stance and the fact you've heard break-in sound worsen over a period before settling to an improved sonic performance.
However that doesn't answer Seandtaylor's very simple but valid point.
That being why do very few folk (I have never heard of an example) report that equipment sounds inferior after break-in?
It is an interesting point.

Spluta, just for curiosity, Er is a force to be applied to distruct dielectric dipole?

Well the one thing that i have learned from being around
electronics my whole life is there is a reason and a
mathematical equation for EVERYTHING. To really diagnose
what is going on someone would have to take all of the
exact properties for all of the different components before
using device and then re-examine ALL of the differnent
component properties again after a period of time. This
could be a very time consuming painfull process.

Seandtaylor99 I think you brought up a really good point.
Why does everyone say it sounds better? I know my current
system sounded better to me.

This is why im gonna stick to my first post:

In my opinion the biggest factor is the material used in
the PCB and component fabrication. There are many different
materials and many different properties such as:

Coefficient of thermal expansion (change in length per unit
in all directions x,y and z thickness. This is different for
all materials. FR4 the most widely used PCB material expands
more in the z than it does in the x,y.

Also moisture can play a part in the whole process. I have
seen PCB's not function at all because they werent baked
long enough. And where you live and how much humidity
can play a part in performance. For example I have done a
lot of work for the Dept of Defense and we had to use
conformal coating on PCB's to be used for ground and air
applications. Sometimes PCB's have to be moisture proof.

Dielectric constant Er changing as materials are burning
in could also play a part in burn in.

These are mostly current flow issues not component drift
issues. I think over time the likely cause of the sound degrading will be component drift.

Im not saying im right or anyone is wrong.

Thats my story and im stickin to it!

Seandtaylor, I would respond to your question in this manner. Since I have no solid engineering proof of this phenomenon, I can't answer in terms of data. But I can point to the several posts on this thread where listeners who did not believe in break-in, were converted when they actually heard the phenomenon, even if they couldn't explain it. So, even though these particular individuals would have been psychologically pre-disposed to not hear the differences, they still heard them.

Regarding why nobody seems to hear "reverse break-in" where things start sounding worse with break-in time, it does happen, but then often goes back into the good sound again, as break-in time progresses. I have heard this happen and have heard others report the same thing. My gut feeling is that there is something happening to the equipment that is changed as electricity flows through it. Exactly what it is, I don't know, but I do hear it, and feel sure that it exists as a physical manifestation, and not a psychological one.

The reason I feel sure about this, is that I have, on many occasions, auditioned new items which I had no knowledge of. I had no way of knowing whether they would be good or bad or indifferent. I could tell the difference, good or bad, in these items. In some cases, even though I wanted to like an item, I disliked the sound of it. So I think that the psychological implications are really not valid.

About break in, now that I have concluded that I can hear differences in equipment, and am not self-deluding, then I can feel sure about my observations in the break-in arena. And I do hear changes taking place with time. I cannot fully explain every phenomenon that I observe, but that does not mean it isn't happening.

Thanks Twl. Perhaps my system or ears are not sufficiently sensitive to hear difference ... I fully accept that this is a possibility.

You know, there's one post above that raises a question that has been on my mind regarding this issue .... "why does everyone report the sound improving during break-in ?" If break-in is a purely electrical phenomenon then wouldn't we have a good proportion of components sound worse after break-in ? However, if the effect is in large part psychological then this would go some way to explain why everything sounds better after break in since our brains are wonderfully adaptable to new experiences.

Now I'm not posting this to provoke the "believers", rather because I think it was a very interesting point.

Actually, this is not a relativistic, everyone has his own philosophy matter. Either "break in" or other audio phenomena are real--in the sense that they can make an objective (if not necessarily measurable) audible difference--or not. It might be true that some people cannot hear such differences, but this doesn't mean that there are no differences. If they can't hear purported differences, they may well be more skeptical that there objectively are such differences. But this, too, is not a philosophical or personal values/beliefs matter: either their skepticism is warranted or not. Of course, if they can't hear purported differences, then the differences will make no subjective difference to them, in which case it wouldn't matter to them whether the phenomena are objectively/not merely psychologically real.

If we could measure the "break-in" factor by some electronic means, then everyone would believe it, right? The main argument here, that I see, is that if there is no measured quantification of this phonomenon, then it is some sort of "psychological effect", or "self delusion". Isn't that what it is really coming down to? Some people only believe in measurements, and some people believe their ears. Same old story, using a differently phrased question. The same thing could be said for any piece of audio gear. Why buy a $50k audio system when a shelf unit has better specs and plays the same music? Any improvement in sound over the $129 shelf system must simply be "psychological". We are simply convincing ourselves that our high$$ systems sound better. There is no break-in, cables don't sound different, power conditioners can't make a difference in sound, tubes are "euphonically distorted", blind testing is the only true way, etc, etc, etc.

I agree with Seandtaylor's statement above. Let's agree to disagree. This is an argument that has its basis far from audio. It is in the individual's belief system. Some prefer to trust the limited measurement capacity of others, more than they would trust their own ears. Fine. Other people would rather trust their ears, than the limited measurement capacity of others. Fine too. The decisions made will directly affect the sound quality of each person's system. They will have to live with their philosophy/choices. My choices only affect what the results of my system will be, and nobody else's. The same is true with Seandtaylor's system. We promote what we feel is correct, and others can make their own decisions as well. Both of our viewpoints, actually, are made from a desire to communicate what each of us feels is a valid viewpoint, in a desire to help others with their decision making. Neither Seandtaylor or myself, would make these statements, if we didn't care about helping other people enjoy their systems, and possibly save money. We just have different ideas about how it should be done. That's all. Everyone can make up their own minds about what way they want to go.

Thanks, Spluta
This link proves that electric and electronic components wear out within time and break-in time is infinitessimaly measurable.
The reliability issues have to be sought for different purpouses whether it's for aircraft, hospital, audio or any different type of electronics.

I have bad ears. I can't hear the difference between electronic components or cables with 3 hours on them or 300 hours. However, I will attest to the fact that the speakers I purchased changed markedly (for the better) after 200 hours on them. I was not the only person who noticed it. Fresh ears who heard them out of the box and then again 6 weeks later commented on how much better they sounded from previous listening.

Mrd, thanks for your honest and incredible story. Naim should back their stuff up and give the gut a full refund. Yes, every lab should be fair in what they sell. Why? For all their GIGANTIC HYPE, they and the "hi-fi" mags print out. Of course a 25% return fee is reasonable. ...Where's Bwhite when our camp needs him most. We could use some reinforcements. Hey Marakanetz very good, easy to understand explanations. Truth will prevail.

A good friend of mine decided to have an upgrade and purchased a Naim system (5 series, pre and power, CD and flat cap) rushed back from the shop, plugged it into his existing Castle speakers in the hope of audio nirvana. It sounded appalling. We both sat there open mouthed in disbelief. He was so upset he contacted Naim who told him it would take up to 1 month (24hr's a day) to sort itself out. 12 months later and it still does'nt sound perfect to my ears.

Last link i posted was wrong this one should work.
The author brings up some good points.

http://www.ece.cmu.edu/~koopman/des_s99/electronic_electrical/

Drubin .. sometimes changing cables can improve the connection. A connection left in place for a long time can be prone to oxidation and dirt. I have had this experience once or twice when my system has had to be moved after several years of no changes. Also cleaning terminals with contact cleaner and replacing cables can have a profound effect.

Actually, I sometimes prefer the sound of a component when I first put it in the system to after it's been in for a while. (This my be related to "change" and not to break in per se.) With cables, for example, I have had the experience of making a change and feeling it was revolutionary ("Now I see what I've been missing all this time!!!" blah blah), only to wake up the next morning to a system that sounds rather unremarkable. I think there is a huge amount of psychology going on with much of what we hear in our audiophile adventures.

You ever notice that everything always sounds better after its broken in? How could this always be the case?

I found some pretty good info on net:

It really isnt that complicated once you understand
there are SO MANY variables. I will post more info
as i find...

http://www.ece.cmu.edu/~koopman/des_s99/electronic_
electrical/

Redkiwi .. here here! Some think burn-in is in one's head. Others think it's in the equipment. Neither side appears to have presented conclusive evidence (electrical measurements, or psychoacoustical studies), so lets all be happy to differ. So long as we're all pleased with the end result.

And are we just arguing about how many angels fit on the head of a pin? Which ever it is that is burning in, the point is we have to be careful to spend time with components before we make judgements. This is what makes this hobby so hard, and why we need to listen with open minds to the experiences of others - and not dismiss experiences of others through lack of proof.

I think # 3 would be closest.

Except that I would expect DIGITAL components to fail before audibly changing.
And PASSIVE components would be the most likely to
drift before failing.
80% of all PCB failures are do to solderjoint problems. When the components with the solderjoint problems are replaced they have new solderjoints and most of the time the problem is blamed on components. Not true.
As far as tubes go.. I cant comment.. I dont know reliabilty. I do have tube guitar amps but havent heard a audible difference yet and no failures.

I have had audio equipment play the same (not very well)
for 20 years.

So the answer is all of the above.

Geez nobody answered my questions, I still want to know:

1) does break-in stop after a while or is the process continuous such that the component will sound only better as time passes; or
2)does it reach a plateau that goes on forever;or
3) does it get better as it burns-in up to an apex and then starts deteriorating until such time the component sounds like s..t.

BTW I will not hold the fact that anyone is an engineer against him/her.

In an ever changing world, life is rough.

Good day.

I am an Electronic designer. Mostly high speed digital
and alot of analog/digital mixed signal stuff. Up until
about six months ago i would have said there is a break
in but it should be pretty quick (for electronic gear)for
things to stabalize.

But now that I have burned in a Bel Canto EVO6 i will
say that i was amazed at how long it took. The documentation
said about 40hrs. I heard subtle differences all the way
to 300hrs. The dealer i bought from said anywhere from
100-200. Before i went thru it i would have never guessed
it to take that long.

In my opinion the biggest factor is the material used in
the PCB and component fabrication. There are many different
materials and many different properties such as:

Coefficient of thermal expansion (change in length per unit in all directions x,y and z thickness. This is different for all materials. FR4 the most widely used PCB material expands more in the z than it does in the x,y.

Also moisture can play a part in the whole process. I have
seen PCB's not function at all because they werent baked
long enough. And where you live and how much humidity
can play a part in performance. For example I have done a
lot of work for the Dept of Defense and we had to use conformal coating on PCB's to be used for ground and air applications. Sometimes PCB's have to be moisture proof.

Dielectric constant Er changing as materials are burning in could also play a part in burn in.

The difference is with a most products or anything else Analog or Digital. If there is too much noise or clock jitter or whatever the case may be the device wont work and sometimes even if its noisy and it works we dont hear it.

With audio especially the high end stuff WE HEAR EVERYTHING.

One of the reasons i went with the Bel Canto is its a solid state device and very efficient so they recomend leaving it
on for sonic stability. It works extremly well. I love it.

So i cant put my finger on why Exactly and i certainly dont
claim to have all the answers all i can say is i have ABSOLUTELY heard the differences. But then again I could be ABSOLUTELY nuts like some of the other audio people who swear by certain things.

Best regards to all..

all doubting Thomas's STILL sound the same!

Marakanetz's post is right on, 100%. Only exception is that i believe there is not even one second breakin time. It'll sound the same the second you turn your component on til the day she dies. Why should audio equipment be the only electronics that needs breakin time. An airplane does not fly any better after 1000 hours of fly time, i'm afraid there is 1000x's more electronics in a plane than in your cd player.

Jayarr-I did that.
It doesn't prove anything except to me!
Which doesn't make other findings wrong.
Why can't people have confidence in their own findings and live and let live?
It's a simple solution.

Jayarr,
Seems to me the best way to find out whether or not what is going on is brain acclimatization or equipment break-in is to buy a new unit and play extensively for the first day taking notes in the process. Play continuously at low volume for 2 weeks without listening.After 2 weeks, now listen and compare notes. I know, aural memory is notorious fickle but at least this is a relatively easy way to try to examine this phenomenon.

I don't understand the naysayers' demand for proof. Surely, it's not that hard to do listening comparisons of same model components, one "broken in" and the other not. In any case, how could science possibly confirm or disconfirm whether there is an audible difference to a listener? Wouldn't a listener's ability consistently to distinguish the components constitute sufficient "proof"? I have heard a pronounced difference in a number of components--cables, amplifiers, etc. Can I prove this? No. Do I understand any scientific principles or phenomena that would explain this? No. I also can't "prove" that my Acoustic Zen Satori cables sound better than my old AQ Midnight III, or that my Linn Karik cd player sounds much better than my old Adcom GFP-750--but they do. I suspect that the same crowd who used to argue that digital can't make a difference, then cables can't make a difference has moved on to break in can't make a difference. It's a tired move--which isn't to say that some things can't and don't make a difference. Listen for yourselves.

rbnl ... are you sure that Boeing's burn in doesn't relate to safety ... that is, electrical equipment is most likely to fail during the first few hundred hours. All manufacturers of safety-critical electronics perform such burn-in to prevent failures in the field.
Or perhaps there is self-calibrating software in their equipment ? This is also quite likely.
Either way I think that aircraft electronics and a simple transistor amplifier (or CD player) are rather incomparable.
Not to say it doesn't exist in audio, but I don't find your argument persuasive.

Redkiwi,
some people do understand it and some people don't and still believe that there is a break-in of electrical components and wires.
truly, nothing has to be scientific to prove that break-in crap.

The psyche needs more settling time than components from an electrical engineering standpoint. Arthur

Just like anything in life, everything have a settling time
before it stabilizes. This include our phychological mind
as well as the components itself.

Being a true scientist, I do not need a scientific explanation in order to observe something happening. Here's a little experience I had with a cable, from which you can draw any darn conclusion you like.

I was putting a new system together and using Alpha Core MI2 Python Speaker Cable. I perceived the system too sound a little too warm and lacking immediacy. I then bought a pair of used Coincident TRS speaker cable, in the expectation that it would eliminate the problem. The TRS was put in the system on a Thursday, and immediately I perceived the sound to be thick and lumpy in the bass, with some thickness in the mids too. This was directly after listening with the Alpha Core in place. So the sound seemed to go noticeably in the wrong direction when the TRS was hooked up.

By Saturday I was perceiving the sound to be opening up and beginning to provide much more detail and more articulation. Round about Saturday evening the I perceived the sound had gone too far and that the upper mids were etched and dry. I persisted with the cable through to the following Thursday but was getting frustrated at how I was enjoying none of the music. The TRS was now consistently irritating me with an apparent harshness in the upper mids, almost unlistenable. I was not surprised at the change in apparent sound since I have experienced it before with second-hand cables that had travelled thousands of miles but I was hating it so much, and had hated it every day for 5 days, that I took the TRS out and put the Alpha Core back in. The Alpha Core sounded to me exactly as I remembered it - nice but a little too warm and lacking immediacy - but mercifully musical and very welcome after the horrid experience with the TRS.

About a week or so later I put the TRS back in the system. It sounded pretty good to me immediately - more detail than the Alpha Core and just as musical - and it seemed to get better over the next three days. After a week I was very satisfied with it and felt the system was sounding just right - which it has continued to do over the months since then. So I had to try the Alpha Core again - sure enough the Alpha Core sounded to me exactly as before. But going back to the TRS, the perceived improvements in detail, immediacy, etc were noticeable, and really made the system boogie. No perception of harsh upper mids at all - totally gone.

So how come the perceived sound of the TRS moved about so much? It appeared to go in one direction, then another, then wound up on the button! Yet the Alpha Core, despite being stored did not seem to change at all.

Funny thing though, my wife observed the exact same phenomena that I did - noticing each change that I described above. She wanted me to ditch the TRS but now agrees it is better. Yet she listened only about 25% of the time that I listened for. So if the effect is psychological, then either; my wife needs 75% less time to get used to the sound of a new component than I do; or elapsed time is the factor not listening time; or my wife senses how I feel about a component and, unprompted, manages to state what I think (could be true, these females are perplexing indeed "life Jim, but... " thinks... maybe she fakes in bed too..); or, perhaps something about the sound really did change. Each of these explanations is quite fantastic given what we know. Hence, perhaps, the answer lies in something that what we do not know.

I've noticed that on pieces of aircraft electronics there is a sticker saying:'burn-in completed'. Would the likes of Boeing bother if it didn't matter? I think that electronic components may work and sound better after break-in because the prototypes were evaluated by the manufacturer after break-in. So, in order to hear what they heard, you need to break it in. Another thing I have noticed is that an amp I once built needed recalibrating after having been used for a while. So apparently something had changed.