well my point was that the components in different speaker models/lines/production runs can vary slightly so that you can see a difference in one set of speakers but not any of the rest. i.e. some speakers can "break-in" more noticeably while others appear the same.
thanks for explaining bipole/dipole/tripole for me, however i was already aware of the differences, and i think what you experienced has little to do with the speakers being of that nature and more to do with the components of each. in a perfect world one could find a whole set of speakers that matched each other perfectly forever and lasted forever and sounded the same forever, but unfortunately things change with time. on the other side of that, sometimes things change for the better instead of worse, i prefer the sound of my system now much more than when i first got it (not all at the same time, but in relation to new vs now condition at least). hopefully your speakers dont continue to keep changing dramatically or i presume that could become bothersome very quickly.

it is always a good idea to "check" your equipment every so often to ensure everything is where you prefer it to be. the significant other can push some buttons when she gets confused and you notice that something isnt quite the same, but cant put your finger on it. or better yet decide to move your speakers so she can clean around them and then you notice one day that they are all out of place. not that i get that anymore, but in other houses where space was tighter i did.