A speaker includes a base, a diaphragm, a separating module, a first electrode set and a second electrode set. The base and a porous structure are formed a cavity. The diaphragm is disposed in the cavity and includes a first part and a second part. The separating module is located in the cavity and contacts the diaphragm to separate the cavity into the first and the second chambers. The first electrode set disposed in the first chamber is connected to a first sound source signal, such that the first part of the diaphragm is vibrated and the first sound source signal is exported from the first chamber. The second electrode set disposed in the second chamber is connected to a second sound source signal, such that the second part of the diaphragm is vibrated and the second sound source signal is exported from the second chamber.