The utility model relates to a
sound box technical field especially, it relates to a
sound box, including casing, speaker and passive
radiation subassembly, be equipped with the installation cavity in the casing, be equipped with the first through -hole of communication with the installation cavity on the casing, speaker is worn and is equipped in the first through -hole, passive
radiation subassembly includes
passive radiator and exhaust piece, exhaust piece includes installation part and at least one
exhaust pipe, installation part is equipped with the exhaust chamber in, exhaust chamber is equipped with the opening towards speaker,
passive radiator includes diaphragm, folded ring and support, diaphragm and speaker are arranged along the first direction interval, folded ring sets up around diaphragm, support sets up around folded ring, folded ring is connected in diaphragm and support, support links to each other with the indoor wall of exhaust chamber, one end of
exhaust pipe links to installation part, the other end of
exhaust pipe is equipped with the exhaust port of the outer surface of casing exposed, the total area of all exhaust port is consistent with the area of diaphragm of
passive radiator. It is convenient for design and manufacture.