A speaker includes: a diaphragm; a coil directly or indirectly attached to the diaphragm; a pair of conducting lines connecting electrically with the coil; a yoke having one pair of longer side portions, and another pair of shorter side portions; a frame disposed between the coil and the yoke; and an inner terminal provided on an area on a straight line extended from the longer side portion of the yoke, and electrically connected to the coil.