Burning/running in, fact or fiction?

Burning/running in?

  • Fact?

    Votes: 21 42.0%
  • Fiction?

    Votes: 29 58.0%

  • Total voters
    50
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In my last thread I asked what burn/run in times should be expected of new equipment, I realise now that I should have actually asked if folk believe it to be fact or fiction, so here goes....



Do you see burning/running in of new equipment as fiction?

Or;

Do you see burning/running in of new equipment as fact? If so, what would you say is to be expected and after what amount of time?

Namely in;

1. Solid state amplifiers
2. CD Players
3. Speakers
4. Interconnects
5. Speaker cables



I'm undecided myself so looking for as broad an answer as possible. I'm not looking to start a 'post war' though, so please refrain from attacking others for expressing their opinion, afterall, they're only opinions.


Thanks
 
AX tech editor
Joined 2002
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I'd expect some change with valves, though (for better or for worse).
Apparently electrolytics need to be "formed" too.

It can be argued that with tubes it's not burn in as such but normal wear and tear, that deminishes the performance. I believe most people expect burn-in to somehow improve performance.

Electrolytics need to be formed, yes. Could probably be seen as a form of burn-in.

Don't forget that the original meaning of burn-in was the process to weed out early failures in equipment ('infant mortality'). You would fire up your amp for several hours or days and if it survived, it was deemed to be reliable and thus burned-in. With expensive equipment, it is often done in the factory to avoid shipping products that fail within a few days at the customers place. Mil spec equipment is routinely burned-in.

jd
 
It can be argued that with tubes it's not burn in as such but normal wear and tear, that diminishes the performance.

Although this is true, there is also a "burn in" process whereby the getter sweeps up some of the residual gas in the first few hours of operation. The grid current decreases and (sometimes) cathode emission increases. This is one reason why tube power amps have to be rebiased after a few hours, but then the bias is stable for a long time thereafter.
 
Don't forget that the original meaning of burn-in was the process to weed out early failures in equipment ('infant mortality'). You would fire up your amp for several hours or days and if it survived, it was deemed to be reliable and thus burned-in. With expensive equipment, it is often done in the factory to avoid shipping products that fail within a few days at the customers place. Mil spec equipment is routinely burned-in.

jd

Great reply, I never knew that.

Thanks
 
AX tech editor
Joined 2002
Paid Member

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It's called the bath tub curve....

jd

...and it is why the extra-cost service warranties offered here in the US by big box electronics retailers are a rip-off and the most profitable item they sell. Things tend to either fail quickly, thus falling under the manufacturer's warranty, or after a very long time, thus falling outside the extra-cost extended warranty.

(I took the liberty of fixing your typo)
 
getter

Although this is true, there is also a "burn in" process whereby the getter sweeps up some of the residual gas in the first few hours of operation. The grid current decreases and (sometimes) cathode emission increases. This is one reason why tube power amps have to be rebiased after a few hours, but then the bias is stable for a long time thereafter.

I know of some people who put tubes from old surplus stocks into the kitchen oven for the same reason.
 
Member
Joined 2006
Paid Member
In one of my previous life’s I was a QC (Quality Control) geek and I can confirm that the points made by janneman are a fact. When I performed QC inspection and analysis for a major mainframe computer manufacturer the commercial burn-in specification to spot infant mortality was 24 hours in a heat tent (closed off room with observation windows) operated at 100f (37.7C). The mil-spec stuff went for a 72 hour burn-in and vibration testing to boot. So – burn in will help with weeding out weak components that are bound to fail early in life.

I believe that the main point of this survey is does “burn-in” help the equipment being “aged” actually sound or perform better when compared to gear that has not undergone “burn-in”. As most have already replied – for mechanical things such as speakers it can make a big difference. This aspect is often seen in statements about how much the sound improves after a bit of “being played” for awhile and can be proven subjectively by listening test and objectively by measurement.

Electronic gear is a bit of a mixed bag but when all is said and done I will go with – “yes” it makes a difference. I have found this to be true especially with tube powered amplifiers and receivers and the effect is measurable with the proper test gear and testing process. For digital electronics I haven’t observed any improvement with a couple of exceptions – and that would be high accuracy clock and timing circuits and oddly enough switching power supplies. Trust me – high power SMPS fur-sure need time to “bake-in” and become stable.

I could continue with examples from high power radar and radio transmitters etc. – but the point will come out the same – yeah – my many years of experience and training have taught me that “burn-in” makes a difference, and it can be measured. ;)
 
1. I don't know. But most likely within reason No.
2. I don't know. But most likely within reason No.
3. Yes/True - but some need it more than others
4. I don't know. But most likely within reason No.
5. I don't know. But most likely within reason No.
 
In one of my previous life’s I was a QC (Quality Control) geek and I can confirm that the points made by janneman are a fact. When I performed QC inspection and analysis for a major mainframe computer manufacturer the commercial burn-in specification to spot infant mortality was 24 hours in a heat tent (closed off room with observation windows) operated at 100f (37.7C). The mil-spec stuff went for a 72 hour burn-in and vibration testing to boot. So – burn in will help with weeding out weak components that are bound to fail early in life.

I believe that the main point of this survey is does “burn-in” help the equipment being “aged” actually sound or perform better when compared to gear that has not undergone “burn-in”. As most have already replied – for mechanical things such as speakers it can make a big difference. This aspect is often seen in statements about how much the sound improves after a bit of “being played” for awhile and can be proven subjectively by listening test and objectively by measurement.

Electronic gear is a bit of a mixed bag but when all is said and done I will go with – “yes” it makes a difference. I have found this to be true especially with tube powered amplifiers and receivers and the effect is measurable with the proper test gear and testing process. For digital electronics I haven’t observed any improvement with a couple of exceptions – and that would be high accuracy clock and timing circuits and oddly enough switching power supplies. Trust me – high power SMPS fur-sure need time to “bake-in” and become stable.

I could continue with examples from high power radar and radio transmitters etc. – but the point will come out the same – yeah – my many years of experience and training have taught me that “burn-in” makes a difference, and it can be measured. ;)

Very interesting response.
Thanks
 
As the thread starter, I guess I should give my tuppence?

In my experience, apart from speakers being 'bright' out of the box but toning down after a couple of hours use, I haven't heard any benificial outcome from running any new electrical equipment for any amount of time, be it hours or weeks.

Having said that, most often than not when I have purchased a new amp/cd player or cable, the salesperson has said "give it time to run in". Some of the sellers were the shop owners themselves who predominantly sell high end gear and have done for many years. Why could that be? Surely when you work with something everyday you become an expert in that field? Could it be that in the 'old days' when components weren't as hardy or as stable as they are today, folk have simply carried the expectation on?

Who's right? them, me or you? Truthfully, I don't think there is an answer, just a varied opinion.
 
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