Passive radiator (speaker)

The active loudspeaker is a normal driver, and the passive radiator is of similar construction, but without a voice coil and magnet assembly.

[6] Passive radiators are tuned by mass variations (Mmp), changing the way that they interact with the compliance of the air in the box.

The weight of the cone of the passive radiator should be approximately equivalent to the mass of the air that would have filled the port which might have been used for that design.

This notch occurs at the passive radiator's free-air resonant frequency and causes slightly poorer transient response.

Passive radiator speakers are only slightly more complex to design and are generally more expensive as compared to standard bass reflex enclosures.