Full Title

Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators (electro-acoustic transducers such as loudspeakers, microphones or gramophone pick-ups H04R; piezoelectric, electrostrictive or magnetostrictive devices with mechanical input or output, e.g. actuators or sensors, H10N30/00, H10N35/00) > Constructional features of resonators of material which is not piezoelectric, electrostrictive, or magnetostrictive