The drivers of most speakers except for Meadowlark, Vandersteen and a coupl of others are out of phase due to the high order crossovers most commonly used.
Aren't passive radiators out of phase?
Passive radiators seem like a great idea, but they must be out of phase with the driver. Yet, you see them on some pretty good speakers, such as the Sunfire subs. All I can think is they provide a spring-board, storing energy for the driver. Still, any sound produced by the PR is out of phase though. Any thoughts?