a frame;

a vibration system including a diaphragm with a dome in a middle thereof and a suspension surrounding the dome, and a voice coil for driving the diaphragm to vibrate and generate sound;

an FPC fixed to one end of the voice coil away from the diaphragm, including an internal fixed part fixed on the voice coil, an external fixed part fixed on the frame and an elastic part connecting the internal fixed part and the external fixed part;

a magnetic circuit system including a yoke engaged with the frame, a magnet fixed on the yoke, and a magnetic gap; wherein

the dome includes a protruded platform recessed from a surface of the dome away from the voice coil toward the voice coil;

the internal fixed part includes a first fixed part connected to the elastic part, a second fixed part bent and extended away from the diaphragm from the first fixed part, and a third fixed part bent and extended from an end of the second fixed part away from the first fixed part toward the voice coil;

the voice coil includes an upper end surface toward the diaphragm and a lower end surface away from the diaphragm; the upper end surface is fixed on the protruded platform, and the lower end surface is fixed on the third fixed part;

wherein the lower end surface is fixed to a surface of the third fixed part facing the voice coil.