A compact loudspeaker enclosure combines planar type devices for high
frequency sound reproduction and cone type active devices for low
frequency sound reproduction. The low frequency cone type transducers are
mounted in baffles between forward and rear enclosed spaces and thus do
not directly radiate into the environment. The first enclosed space is
acoustically coupled to the environment by the planar device which is
mounted between the first enclosed space and the environment with one
major face mounted to radiate either directly into the environment or to
be horn loaded. The planar operates as a passive radiator to the LF
devices at low frequencies and an active device above a crossover
frequency.