The ZetaProbe determines zeta potential the electrokinetic sonic amplitude (ESA) effect. Samples are placed in a cell containing two electrodes and the electric field (of the order 100 volt/cm) is applied at a very high frequency. The sound wave generated from the colloidal suspension is detected. The ZetaProbe also features a built-in titration apparatus. The automatic titration offers unattended rapid isoelectric point determination, as well as optimum dispersant or flocculant level control.