Quote Originally Posted by Ajani
One thing I should clarify is that getting more in tune with the sound of your system over time is not the same as 'imagining a difference'... it doesn't mean you're losing your mind...

I believe some part of burn-in is not about the equipment burning in, but you burning in (so to speak)... So on first listen, there is no way you could have heard all the detail the system was offering, but a year down the road, you can pick up all those minor details you were missing out on...
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The theory that we accomodate ourselves to the characterist sound of our system is just that: a theory. Perhaps it is a testable hypothesis though I'm not a scientist and can't think of how to design a relevant, DBT-type experiment. However I suspect it would be about as difficult as for burn-in.

There are times when I've been pretty sure that I heard burn it. One of the more obvious was the case of brand new vacuum tubes -- definitely (it seemed to me) a big difference after a dozen hours or so.

The lengthiest burn in that I believe I heard was from my Panasonic SR-AX25 receiver which as at least 500 hours. I have never noticed any burn-in on cables; (in fact, I have rarely notice any sort of differences among cables in the low- to high-medium price range, Blue Jeans cable versus Kimber PBJ for instance).