Well, thank you all for your input and replies. I guess I touched a nerve with this topic. Sorry about the disagreements. We're all at different experience and educational levels when it comes to high end audio, eletronics, sound, etc.
My conclusion is that it's probably a combination of your own ears and brain acclamating over time plus the materials inside the speakers themselves are perhaps changing a bit. Maybe the Kevlar in my B&W's become less stiff for example. Just a thought. I'll go along with the first responder of between 100-200 hours. I have to tell all of you that when I installed a PS Audio power port some months ago and replaced the junk builder's grade eletrical outlet, I heard and continue to hear a marked difference in the information and detail coming from my loudspeakers and amp. I know this has nothing to do with the "break in period" topic but to if anything caused the sound to improve considerably, that did it. I actually installed a 2nd one since my SW is plugged into a different outlet from the amp. Good stuff gents.
My conclusion is that it's probably a combination of your own ears and brain acclamating over time plus the materials inside the speakers themselves are perhaps changing a bit. Maybe the Kevlar in my B&W's become less stiff for example. Just a thought. I'll go along with the first responder of between 100-200 hours. I have to tell all of you that when I installed a PS Audio power port some months ago and replaced the junk builder's grade eletrical outlet, I heard and continue to hear a marked difference in the information and detail coming from my loudspeakers and amp. I know this has nothing to do with the "break in period" topic but to if anything caused the sound to improve considerably, that did it. I actually installed a 2nd one since my SW is plugged into a different outlet from the amp. Good stuff gents.