A generalized transfer function is introduced, defined as the ratio of the phasor of the electrode potential to the phasor of the applied potential. The occurrence of a maximum of this transfer function at a particular frequency is defined in this work as electrochemical resonance under potentiostatic control. The electrochemical resonance conditions are derived for an electrochemical system in steady state of a stable focus type, characterized by an eigenfrequency omega(0). The resulting relations are explored and compared with the response of the electric parameters (impedance and admittance). The theoretical considerations are supported by experimental findings. (C) 2011 Elsevier Ltd. All rights reserved.