What Exactly Does "Burn In" do for Electronics?

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.

"Changing out parts for different effect has nothing to do with so-called burn in. The same issue would apply."

Like I said, don't take my word for it. Call some manufacturers and see what they say.

As I see it, it can be expected that by the time developmental testing is completed on the prototype of a new design, including final tweaking/voicing of the design, the prototype is likely to have accumulated a MUCH greater number of hours of operation than production units accumulate prior to leaving the factory. Both as a matter of necessity, due to the nature of the development process, and because the designer will want to assure that final tweaking/voicing takes into account any possible breakin phenomena.

Therefore if in fact breakin phenomena occur for a given design over a number of operating hours that is greater than the number of hours of operation of production units prior to shipment from the factory, those phenomena will continue to occur after the component is placed in service by the end user. And the component will not perform as its designer intended until after some period of use by the end user.

I would be very surprised if any of that were not the case, particularly when it comes to speakers, cartridges, AND major electronic components. So I am in essential agreement with ZD on this point.

Regards,
-- Al

06-22-14: Zd542
"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.

Ok if this is true, then this means all production units sent out that are not "burnt in" have been purposely miss-adjusted/calibrated for currents, bias, dc offset etc, NOT for the best ideal performance.
Hoping then that all these parameters of adjustments will all come together after the customer has "burnt it in" for a few weeks??? I think not.

Cheers George