Burn/Break-in

I can see the idea of burn in working for a few things , mostly electomechanical , such as speakers, headphones, cartridges, etc. I know that electrolytic caps can also change their properties especially Aluminium foil ones as the oxide layer builds up with use.
I often wonder whether some of this 'burning in' is just components 'warming up'to their normal and stable operating temperatures. Certainly the electical properties of certain materials will change with temp , eg resistance values, magnetic values.

As far as cables burning in I've never actually noticed any obvious night and day differences.
I notice that my incredibly crap standard fit Car stereo sounds particularly crap if i get into the car in winter and it is really cold, as the car warms up inside and the speakers get a bit of exercise with use driving along the sonic quality of the sounds rises to an almost barely acceptable level - (Audio it is - Hi-Fi it is not ).

I should add that whether i believe in burn in or not I always do it anyway, and have done for years - just in case it does work.

For somebody who is slightly sceptical over the various claims made for different cables, etc, my collection of digital I/C's went up to 4 this morning after the postie called. I got one of Mark Grants cables ( AV Forums). It seems to be very well made indeed and has been burning in on repeat CD all morning - well you never know.

 

Good question!!

Is burn-in just a figment of the imagination or is there real science behind it? With regard to my speakers I can definitely say that they sounded so bad when new that I almost returned them to the dealer. The frequencies were all over the place but after 200 hours or so, things settled down, and the speakers started to sound more like the dealer's pair that I had on home demo. However, for cables and amps etc, I'm not so sure.

One thing I find amusing is the concept of the cable cooker and cable suspenders. In one review that I read, the reviewer mentioned something about putting the cables in a cable cooker to cook and there was a dramatic increase in the cables performance. I almost choked on my coffee when I read that and I relayed that info to Mrs Lawrie who then kindly offered to cook all my cables herself as it would work out cheaper. You've got to admire her sense of humour. So, whilst we are on this burn-in subject, could someone explain what the cable cooker is all about and whilst doing that touch on why cables should be suspended using cable suspenders. Man, what a great hobby eh!





Enjoy the music,

Lawrie.

 

It has to be the mind-meld, Tone, because a magnetic field has zero effect on the crystal structure of the iron core, which remains the same. Moreover, I believe that most transformers use soft iron cores, and this does not become permanently magnetised, because the material itself is non-magnetic. The magnetic field is there solely to induce an electrical current in the secondary windings.

Hi-fi as New Age philosophy, whatever next?

 

Tones, Ok maybe thats that particular theroy discounted, so another one please mate, as to quote a ceratin legend, "when all probable causes are accounted for, then what is left is the unprobable', expect the unexpected
However there are more explainations to this I feel, so you feel that the surrounding magnetic and radiated fields have no bearing on the this at all?, so may an interaction between the flowing electrons through the wires and the resultant field strengths?
I understand your postion Tone, I can't put me finger on it either, but there is a difference, also what about e-core tranys, multi layered & serious giver off's of emf?, a lot of the cheaper gear uses Frame trannys, space ease of placing and cheap.
Sorry Brians a bit clouded to day, too much solder fumes

 

It was Sir Arthur Conan Doyle, speaking through his famous detective Sherlock Holmes - words to the effect of "when you have eliminated the impossible, what is left, no matter how improbable, must be the truth".

I pretend no electronic expertise, I was just answering one question on the effect of magnetic fields on transformer cores, from a strictly materials science point of view. To me, it is conceivable that magnetic fields generated in a transformer could have some effect on components lying within that magnetic field. But then, as I understand it, a transformer is there only to reduce a mains voltage to a lower voltage for the components to handle. The magnetic field will therefore fluctuate only as the AC goes through its cycles, reversing its polarity with the cycle. The combination of the rapid build-up and collapse of the magnetic field, plus the constant reversal of the field polarity, would appear to cancel out the possibility of any permanent effect, as any tendency to magnetise would be reversed in the next cycle one-fiftieth of a second later. Moreover, much of the material in modern solid state equipment is semi-conductor material, relying on the doping of an otherwise non-conducting material. I'm not sure that current can be induced in such materials by magnetic fields (but I don't know).

Of course, the fundamental question is, would any of this produce an audible difference? And how would you know if it did? As I've said before, I do not dispute for one second that you heard a difference. I have never heard these differences, but that may be my failing. However, the scientist in me is interested in knowing why!

 

lawrie,
i heard that em interference is much more pronounced within 1 or 2 inches of the ground if this is the case then suspenders make some sense, especially if you are using unshielded cables. i have tried 'suspending' my speaker cables and it makes a little difference (to my ears) but not enough to really get bothered about.
as for the physical effects of burn in perhaps its - neuron linking here, neuron breaking link there......am i a king dreaming i'm a butterfly or a butterfly dreaming i'm a king....

cheers


julian

 

OK, so how about this theroy: It's all in our heads mate
Please discount this one, because as someone else who was very clever nearly said
"Of two competing theories or explanations, all other things being equal, the simpler one is to be preferred"

 

sorry to intrude again with my clap trap on this issue, praise thee the lord, but......

.....damn, no its gone. I had something in mind, but now i've gone and lost it. A piece of my mind must have travelled East, with my thought picnic in its rucksack.

Now i don't know. Bugger......

......Ok, how about.......Does it give one pleasure deconstructing the universe, or is it merely an instinctive, unalterable life force? I can't claim to doubt that these things are so nicely packaged, like a wooden ship in a glass bottle, firm, unalterable, and magical..... but really.....do you feel more alive to the sound of music as a consequence of this knowledge?

There is evidently only sadness, once it is revealed how the little foldy thing, and bit of pokey stuff weaves its way splendidly into the confined ocean, or is it wonder, i can't remember. But of course, the TRUTH. We shall not be deceived into the miserable stupidity of bowing to the cable cooker.......Newton has proven that my feet are firmly on the floor, and it would be sacriligious to dishonour his supreme reason, to spill the guts of the truth within me, and drift along the madness of the rainbow, blind into the oceans of isobars and voodoo waves.....

As for me, I never really did hear a difference with burn-in, or did i? I can't remember. It seemed reasonable enough, and i warmed to the idea.

Anyway.......

I can't tell the difference anymore. Maybe i don't want to.....who knows.

 

As far as I remember from Snake Oil 101 at school, there is a very valid reason for cable burn in, and it's actually to do with the di-electric and it's structure; after a while, it becomes a lot more uniform in it's arrangement due to energy transfer back and forth between the conductor and di-electric. That makes sense to me, and would explain directionality quite nicely too.

(I'm purposefully being vague here because I don't know all the technical details and don't fancy someone with a more expert knowledge taking the piss).

 

This may be part of my problem, Cookie - I know I don't want to! Then I won't have even to think about all this tweaking business.

 

The dielectric? You mean, the stuff that goes round the wire? The non-conducting stuff that goes round the conducting wire? Was it 1 April that day? I'm a polymer chemist by profession, and I've never heard this one. (But then, that was a long time ago, and Snake Oil 101 wasn't offered in those days, probably because there aren't any snakes in Ireland - St. Patrick clearly had no concern for the future of the Irish hi-fi industry, which explains why it hasn't got one).

 

But dont dielectric have absorbing qualities?

 

Yes. They suck the reason from unsuspecting mortal brains. Beware of really thick cables, cos that's what they'll make you. Really thick

 

Yes, thats the stuff. However, just because it's a insulator doesn't mean enegry tranfer can't happen. Hit a block of Teflon with a bolt of lightning and it doesn't bouce off because it's non conducting, it melts the bastard - Energy transfer. Tiny, very quick enegry tranfer is possible, or so I'm lead to believe. Yes, I could be and probably are, well out on this one.

 

No, i think your right Gambit, and it goes along with capacitors aswell

 

as a student in mechanical engineering I might be able to shed some light in the cooking cables mystery.

When a cable is stept on or otherwise abused, this may cause micro fractures in the material used. I would imagine the object of the cable cookers is to bring the material near the recrystalisation temperature to fix these micro fractures. I have a few second thoughts about this.

1.) I doubt you will reach the recrystalization temperature before melting the plastic around it.
2.) Because the cable is a thin body it will cool down quite rapidly. This can cause the material to become more brittle making the forming of new microfractures easier after the first treatment.

This reminds me of something i read on the Van den Hul website some time ago. It was about "burning in" wire by running a very high current through them. This would eliminate the first point because the cable would be warmed up by its ow resistance, from within, but van den hul also warned for the effect I mentioned under (2.). One was warned that these treatments would have to be repeated ever faster because the treatment, in the long term actually causes the effect that it tries to cure. So this wasn't recommended.

 

I've heard that one too Gambit, and like you thought it sounded at least plausible. Not sure what it has to do with directionality mind, which I'm afraid even I think in b*ll*x.

 

Nobody mention 'Skin Effect' !

:duck:

 

Makes my skin crawl! or is that the wrong effect

 

Cable cooking has nothing to do with Physicaly applying heat to the cable, 'Cooking' is term dream't up by the manufacturer of the said device, depending on which cable your cooking,P/C & speakers cable are subject to a higher/current/ voltage application, the process used generates a wide bandwidth/very fast transient responce, partial square wave form 'spike' that has a ramped frequency responce, this causes changes inside the grain structure of the material, when applied over a given period.
Weather the bollox boys are queing up or not, last week, I'd finished a pair of speaker cables for a US customer, I for got to take them off the cooker & the had 12 hours more than I would normaly give them, the result, dull/lifeless & closed in stage and very curtailed top end, yet the other set (uncooked at that time) a difference beast altogether