To reduce crosstalk or the like between signal wires in a transducer.

The transducer which converts sound waves to electrical signals includes a piezoelectric unit having a plurality of piezoelectric elements each of which converts the sound waves detected on a detection surface to the electrical signals, and a multilayer substrate to which the piezoelectric unit is fixed. The multilayer substrate has the plurality of signal wires which are provided correspondingly to the plurality of piezoelectric elements and transmit the electrical signals output by the corresponding piezoelectric elements, and a shield unit for electromagnetically shielding at least a portion of the plurality of signal wires. In the piezoelectric unit, the surface of the multilayer substrate to which the plurality of piezoelectric elements are fixed and the detection surfaces of the plurality of piezoelectric elements are fixed to the multilayer substrate so as to have an inclination.