To provide an electric signal transducer capable of surely vibrating a diaphragm in tracking with a sound signal.

The electric signal transducer 1 is provided with: the planar diaphragm 2; and a vibration generation drive source 3 capable of vibrating and driving the diaphragm 2, the vibration generation drive source 3 is placed on a rear side of the diaphragm 2, which is supported by a sheet-like member 10 that has flexibility toward its outer circumferential end, the sheet-like member 10 is supported by a rigid body 9 located at the outside of the diaphragm 2 with a gap of a prescribed width with respect to the outer circumferential end of the diaphragm 2, and the diaphragm 2 is vibrated in a facial direction shown in the arrow C being a direction orthogonal to the face of the diaphragm 2 via the sheet-like member 10 by driving the vibration generation drive source 3.