A converter including a transducer layer which moves anchoring points to deform a piezoelectric diaphragm by bending. The converter includes a rigid arm between each anchoring point and a point for securing to the piezoelectric diaphragm to which it is attached, the rigid arm being tensioned between the anchoring point and the securing point and configured to transform movement of the anchoring points into a movement that deforms the piezoelectric diaphragm between bent and less bent positions. The securing point is located at the mid-point when the ends of the piezoelectric diaphragm are secured, with no degree of freedom, in a frame, and the securing point is located at one end of the piezoelectric diaphragm when the mid-point is secured, with no degree of freedom, in the frame.