Physical explanation of amp's break in?

Thanks Sean. Indeed, first time I see so professional and practical *positive* opinion on that matter. I would highly appreciate your opinion about cables break-in: cables are generally simpler 'devices', which offers less room for 'combining'...

I think both emotional and psycho-acoustical components take their part here as well, but as I mentioned in the original post, there are some aspects that cannot be explained just by "delusive perception".

Herman, can initial change of new components be predictable? Meaning, for example, that for a specific type of capacitor, it's value goes down 0.2-0.4% on first X hours of use?

Thanks a lot, Sean!

What's funny here, people tend to consider this as something to "believe in", instead of "know". To believe because "somebody told me", or "he must have MSc in EE to know"... LOL! Here you've got an opinion based on a practical experience and professionally measured data, not just a simplified theory. Instead of asking "educational background" :) , it would be more appropriate to provide a data, acquired on a similarly professional level (not "personal thoughts"), that would just prove the opposite... Should be easy, right?

Paulwp, I hope you accept the fact that components do initially shift their values, in predefined tolerance range? You don't have to call it break-in and it doesn't automatically assume any sound improvement. But if the same kind of components will tend to settle in the same direction, and to achieve their natural point of settling after about the same hours of use, where do you see a contradiction that during design period an "already settled" prototype is evaluated and being worked on, so the aim of the designers is not how it sounds just assembled, but after known and measured period, specifically for the parts used?

Eldar, you're right about the role of Taguchi approach in industry in general, but what should be taken into consideration, is that markets for Sony TVs and hi-end audio are quite different, and so different their consumer's demands. Unlike Best Buy clientele, hi-end audio consumer is interested in "in a margin representing the last few percents of what's attainable", as was mentioned in another thread. For any hobby of this kind (audiophilia, wines, cars, etc) all the joy and satisfaction is expected from those few percents, and not about the rest 97% of normal, mass-oriented, healthy and practical minivan-styled stuff. One of the reasons that cause one to purchase a unit for several thousands dollars is a fact (or at least idea from advertising of that product) that it’s manufactured with “hand-made” approach, sometimes manually tuned – shortly, resulting high price is actually a positive factor here - just opposite to Taguchi direction.

Eldartford, I meant a difference between even very good mass-market product and hi-end. Among TVs I would think about Pioneer in this group, but not Sony. It's not just a matter of "better quality-higher price", it's matter of different markets: I guess under normal circumstances you don't come to Best Buy for your next amp upgrade? If you build a graph Price=F(Quality) on some stage it will go up much faster then before, i.e. a little increment in quality will cost much more money then similar increments before. Here comes audiohile's market. If you don't tweek the product, it'll be declined: as per the same graph, for normal practical approach it's worth to go a little bit down in quality for quite significant difference in price.