To provide a motor-driven speaker in which rigidity of a voice coil is improved even in spite of a shorter elongated shape in a short-diameter direction relative to that in a long-diameter direction, operational defects are reduced to stabilize quality, at the same time, electroacoustic transduction efficiency is improved, and a playback sound pressure level is increased even in spite of a low full height.

A voice coil includes: a bobbin which is formed approximately in a track shape including linear portions of parallel two sides and two arcuate portions connecting the linear portions of the two sides and includes an inner hole, at an inner diameter side thereof, for housing a pole specifying a magnetic cavity of a magnetic circuit: a coil which is wound around the bobbin and formed approximately in a track shape; and two tinseled wires connected to both ends of the coil, respectively. In the voice coil, one end of each of the two tinseled wires is connected with the coil at a lower end side of the arcuate portions of the bobbin and fixed onto the bobbin.