PURPOSE: To endure a high input by circulating a cooling liquid with an oscillatory partitioning plate, a suction valve, and an exhaust valve, which are provided in the rear side of an electric speaker, to cool a voice coil in a speaker system using a CD or the like.

CONSTITUTION: When the diaphragm of a woofer 13 is oscillated to raise the pressure in a cabinet 12, an oscillatory partitioning plate 25 is moved to the inside of a tweeter 14, and the pressure in a tank 24 rises to open a suction valve 23, and an exhaust valve 21 is closed. When the pressure is reduced reversely, the partitioning plate 25 is moved to the outside, and the pressure in the tank 24 is reduced to open the exhaust valve 21, and the suction valve 23 is closed. An internal cooling liquid 32 receives the pressure and is flowed to a bobbin 31 from a small hole 18 opened in a magnetic gap and is brought into contact with the bobbin 31 to cool a voice coil 30. The cooling liquid 32 whih absorbs heat is flowed back into the tank 24 from the second hole 20 of a lower plate 17 and is radiated through a radiation fan 26.