A method of creating localized haptic stimulations on a user includes a wearable device including a plurality of transducers that can each generate one or more waves that propagate away from the wearable device through a medium. The method includes activating two or more transducers of the plurality of transducers, selecting values for characteristics of waves to be generated by the two or more transducers based at least in part on a known impedance of the medium. The method further includes generating, by the two or more transducers, waves that constructively interfere at a target location to create a haptic stimulation on a user of the wearable device, the waves having the selected values.