The present invention relates to the operating principle of a loudspeaker (20) with an induction motor (10). The motor (10) has two magnets (1a and 1b) positioned on either side of a central core (2). The magnets (1a and 1b) thus create two magnetic fields (9a and 9b) doubling the magnetic field detected in the movable armature (4). The magnetic field coupled to the electrical field generated by a fixed coil (5) creates a force in the armature (4), which is linked to diaphragm (7) producing the sound. Thus, by increasing the magnetic field, and therefore the force generated in the armature (4), the performances of the loudspeaker (20) are likewise enhanced.