These speakers feature a tall, thin, and narrow metal ribbon instead of the wide diaphragms found on electrostatic speakers. Rather than charged metal panels like those found on electrostatic speakers, the ribbon in a planar-magnetic speaker is suspended between powerful magnets. A current passes through the metal ribbon, which resonates towards or away from the magnets in order to generate sound waves. This type of speaker does not need to be connected to an electrical system to operate.