Dipole design speaker using a metal ribbon stretched taught between two powerful magnets to generate sound when a signal is sent through the ribbon. Planar-magnetic speakers generate sound from both sides of their ribbon making them dipole speakers (since it is one ribbon vibrating, the two sides are by definition out of phase creating a dipole rather than a bipole speaker). he ribbon is suspended between two magnets. Suspended within the magnetic field, a signal is applied to the metal ribbon. The signal in the ribbon causes it to be repelled and attracted by the magnets generating motion and thus sound. lanar-magnetic drivers are typically used for high and middle frequency sounds. The ribbons are not very efficient at producing deep bass, so most planar-magnetic speaker designs mate a typical dynamic bass driver to the ribbon or ribbons used for the upper frequencies. Due the low mass of the ribbon, planar-magnetic speakers are able to react very quickly to transients and provide a great deal of detail similar in effect to electrostatic designs.