Burn in - a myth?

What is that mechanism?

Initial development of the oxide layer in the electrolytic capacitors? Though I cannot find a reference I thought that was a pretty quick process, but is called out by 110db in the link above as a factor in SQ improvement in new equipment IIUC

When they are new using them improves their properties as the dielectric forms (insulation between the plates) improving SQ.

If someone observes the performance of new components and cables changing over time, is that observation a myth if they can’t/don’t/won’t prove the observation?

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I assembled a mains cable for my DAC with Furutech wire and connectors and am very satisfied with the result.
However I can’t say that I noticed any change in sound over time.
Didn’t try it with Naim gear either as Naim stock cable is usually the way to go. Might be worth looking into…

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I’m sure that Douglas Adams could come up with something spectacular, if he were asked.

He did give us the Pan-Galactic Gargle Blaster, after all!

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It would certainly be open to challenge unless there was objective proof and as this thread as shown with Hi Fi, objective proof can be difficult to arrange.

In my industry we generally install our cables in a particular way and are extremely careful with how they cross, how they are grounded and mixing different types of cable, this is based on measurements, industry standard and bitter experience with faults. I use the same principles when arranging my system at home.

For simple cables I have yet to see any measurable changes post installation and no burn in effects nor have I seen any research paper which objectively supports change in cable properties after a period of time post installation (I am happy to be proven wrong and would love to read a properly researched paper on the subject). The only time I have seen measurable physical changes over an initial period is with cables which are very long (kilometers) and subject to considerable external forces (sufficient to force the armour closer to the conductor).

I can get my head around proper cable terminations, microphonic effects, and proper earth arrangements within cables - but I cannot see how these change over time. Cable relaxing, I am not sure about and if I recall correctly didn’t some manufacturers get a fine for making statements in advertising about cables without having objective studies to support improvements (may be wrong on this, but I am sure some companies have been highlighted for it). But burn in of runs of cable in a home context, that I don’t understand.

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“I dunno.”

Morrisey

Just in passing - you’re obviously not religious. So aren’t I.

I’m not sure what my view is on this subject because I’ve never really taken an interest in it but there are a couple of things that I know happen when a high current is passed through a cable. A) the cable can twitch and B) It can get warm. Obviously physically observing this usually involves very high currents but I’m quite prepared to believe that there are some effects at low currents that we don’t notice. Does a cable moving microscopically “loosen it?” Does a cable that warms and cools microscopically “Become annealed?”. I’m happy to believe that if the molecules have adjusted themselves over several months that this might affect the sound but I’m not sure why it should always be in a good way.

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Work hardening of copper cables is possible I guess is you are constantly bending and unbending it. Annealing though? 400 degrees C is one hell of a current needed to get to that temp. My metallurgy degree and work experience never got me in to the nano level though. :thinking:

As a software engineer I know very little that is actually useful in this area. Perhaps I should rewatch the Antman movies. There’s loads of quantum stuff in that. :grinning:.

I tell a lie, I once managed a product that used “quantum annealing” to work out the most efficient routes for service engineers to move between jobs in their vans. However, I try to forget about that and it’s irrelevant to this topic anyway.

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The pain in my leg is getting worse.

Prove it.

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Touché. So too aren’t I.

Well the question is are they observing a change, attributable to one cause, or is it down to one of the other many possible variables (see my post about 30 back from this one).

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People with one leg often report pain in the missing leg.

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Adding to the above if the mains is noisy I’ve found it can wreak havoc with a listening session. Experienced it many times, one night absolutely sublime the next absolute rubbish nothing has been changed :crazy_face::pleading_face:

In addition to @gthack’s reply, @Xanthe posted this in a previous thread:

BTW your editing of my text lost the fact that the “very much” referred only to the first example, mechanical compliance changes.

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Can normal mains noise in a domestic environment make this much difference?

Sounds more like mood swings, added to changes in mains noise.

Plus alcohol, or the lack of alcohol.

Matin Colloms in his review of the Naim Statement:

MARTIN COLLOMS

Running In
In the earlier stages of evaluation we had wondered how the amp, both pre and power, could possibly improve on the high standards it had already demonstrated after the first few days (following a suitable warm up and the lab bench testing).
However, Naim folklore has it that the final voicing of its amplifiers is not confirmed and signed off until it has passed crucial subjective in-house criteria after about three months of intensive use. As mentioned in the technical section of the main published review (Vol9 No2), Naim favours certain electronic components (especially both polymer film and solid electrolyte tantalum capacitors) for their long term sound quality, particularly in respect of timing, dynamics and definition.

Very awkwardly, these components do not show their best audiophile qualities until they have had some use in an audio circuit, with both correct polarising voltages and audio signals. Otherwise they sound a just little dead, two dimensional, obscured, edgy, and mildly ‘squashed’ dynamically and rhythmically. Such a scenario could not possibly be suspected from first hearing the Statement, since these factors already seemed to be held to a very low level by this point. But as the running in process unfolded it was in just these areas that the Statement got better and better. In any case, this amplifier uses quite a number of those ubiquitous power supply and decoupling electrolytic capacitors, and it is well known that their electrical and audio signatures will only stabilise after many weeks of use.

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The cited explanation for change in equioment performance is not inconsistent with my understanding of a possible mechanism if there is indeed a change in sound. And Naim fine tuning its kit on the basis of listening tests undertaken after a long period of running makes every sense if there is even the possibility of change while things settle.

But whether or to what extent the majority of people other than professional audio experts listening for even the smallest difference can hear the changes due to electronic components “burning in” in real life implementations is of course an unknown factor. Some people certainly believe they can and do, and I have no reason to disbelieve them. That said, whether any perceived change that people tribute to “burning in” is truly due to change in the equipment rather than their ears expecting it or becoming accustomed to the gear, or even due to changes in their hearing, is another question, especially when the comparison is with a memory of sound from some days or weeks earlier.

Regardless of the above, I would have thought that any manufacturer sending their stuff to be reviewed, as opposed to the reviewer buying it to review, would ensure that the equipment was sounding at its best – and if that means running in for three months or whatever first, then why would the manufacture not do that? with the review sample? If they do then subsequent changes heard by a reviewer aren’t due to “burning in”… The above quotation certainly suggests that Naim didn’t run in before submitting for review, or that Martin Colloms assumed they hadn’t.

Some people believe they can’t and don’t.

Some manufacturers are happy to let reviewers receive the same equipment as their customers will receive - and in the same state of burn-in.

Actually, review equipment has often been out in the wild or used in the factory for some time.

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