Abstract: An electrodynamic loudspeaker for use in a magnetic field generated by an external source, the speaker comprising an acoustic diaphragm attachable to a non-magnetic speaker frame at one end thereof; and a voice coil wound on a bobbin attached to the opposite end thereof, the speaker frame being adapted for mounting the speaker within the external field, the speaker further comprising a magnetic field diverter for locally reshaping the external field in the area of the voice coil for improved efficiency, and including provisions for effectuating operation of the speaker in external fields which may be oriented at various angles relative to the longitudinal extent of the diaphragm.