Front driver
In a piezoelectric transducer, a nonresonant component in front of the front ceramic. The front driver applies pressure to the ceramics via the stack bolt. In addition, the front driver couples to the next member of the stack, usually via a central stud. The ultrasonic energy travels out of the front end of the front driver. Details ...
Synonyms — front mass, head mass, emitter
Also see other transducer components.