When a smartphone or smartwatch is submerged or splashed, water gets drawn into the tiny mesh perforations by capillary action. Due to surface tension, liquid droplets cling stubbornly to the speaker diaphragm, blocking acoustic vibration and causing voices and media to sound muffled or crackly.
Our 165Hz cleaner sounds work because 165 Hz closely corresponds to the natural resonant frequency of mobile acoustic chambers. At 165 Hz, the speaker driver excursion reaches its safe maximum displacement, acting like a miniature piston that pumps air through the grille. This kinetic pressure breaks the water surface tension, forcing droplets out through the speaker holes.