Systems and methods are provided for simultaneously determining impedances of a plurality of electrophysiological electrodes. Signals are injected into a first electrophysiological electrode and a second electrophysiological electrode, the injected signals differing in at least one of magnitude and phase. A magnitude and phase of an output of a differential amplifier are evaluated, where the differential amplifier is responsive to outputs of the first electrophysiological electrode and the second electrophysiological electrode. An impedance of the first electrophysiological electrode and an impedance of the second electrophysiological electrode are determined based on the magnitude and the phase of the differential amplifier output.
