Audiophilepure

Read Here

“A passive radiator is something entirely different. It is a driver with no voice coil or magnet. It is usually a round weighted planar driver (flat) mounted with a heavy surround. It is in the same air space as the active subwoofer driver. The passive radiator responds to the active driver moving because the air in the enclosure is pressurized either positively or negatively as the active driver moves. It is not in the same phase as the active driver because it takes a finite time for the passive radiator to respond to the movement of the active driver. This is the case for the Earthquake MiniMe DSP P12 subwoofer.”