A microelectromechanical apparatus for generating a sound, the microelectromechanical apparatus comprising: an array of moving elements (110, 210), each of the moving elements coupled to a mechanical support by at least three flexures (120, 220) each associated with at least one piezoelectric member (130, 230) which is operable to be strained by an electrical field applied to the piezoelectric member, thereby flexing each flexure to which the piezoelectric member is coupled; an electrical wiring, comprising a group of electrodes (140, 240), wherein each electrode out of the group of electrodes is coupled to at least one of the piezoelectric members, such that each piezoelectric member is coupled to one of the electrodes; wherein the electrical wiring is operable to concurrently transfer different sequences of electric fields to different piezoelectric members, thereby controllably inducing movement of at least one of the moving elements of the array perpendicularly to a plane of said mechanical support, while a plane of said at least one of the moving elements remains parallel to said plane of said mechanical support; and a motion restriction mechanism for maintaining a maximal motion distance for each of the moving elements when being actuated via the corresponding flextures and piezoelectric members, wherein the motion restriction mechanism comprises an array of mechanical stoppers (160, 260) associated with the array of moving elements, such that each of a plurality of the moving elements is operative to be constrained to travel alternately back and forth along a respective axis and is held against the mechanical stopper when the electric field applied to the respective piezoelectric member coupled to the respective moving element exceeds a threshold value. an array of moving elements (110, 210), each of the moving elements coupled to a mechanical support by at least three flexures (120, 220) each associated with at least one piezoelectric member (130, 230) which is operable to be strained by an electrical field applied to the piezoelectric member, thereby flexing each flexure to which the piezoelectric member is coupled; an electrical wiring, comprising a group of electrodes (140, 240), wherein each electrode out of the group of electrodes is coupled to at least one of the piezoelectric members, such that each piezoelectric member is coupled to one of the electrodes; wherein the electrical wiring is operable to concurrently transfer different sequences of electric fields to different piezoelectric members, thereby controllably inducing movement of at least one of the moving elements of the array perpendicularly to a plane of said mechanical support, while a plane of said at least one of the moving elements remains parallel to said plane of said mechanical support; and a motion restriction mechanism for maintaining a maximal motion distance for each of the moving elements when being actuated via the corresponding flextures and piezoelectric members, wherein the motion restriction mechanism comprises an array of mechanical stoppers (160, 260) associated with the array of moving elements, such that each of a plurality of the moving elements is operative to be constrained to travel alternately back and forth along a respective axis and is held against the mechanical stopper when the electric field applied to the respective piezoelectric member coupled to the respective moving element exceeds a threshold value.