An inertial sensor is described that has means for improving quadrature rejection The sensor is of a ring type, driven by a driver circuit, the sensor further comprising primary and secondary portions having corresponding signal pickoffs. The primary pickoff signal amplitude is controlled via an automatic gain control, the primary phase lock loop and VCO locks to the resonant frequency to provide the clocks for the synchronous detectors, the primary pickoff signals via the primary phase shift circuit is provided to the primary driver, the secondary pickoff signal being input into a detector circuit capable of detecting motion in the sensor. The secondary channel comprises a series of circuits that when operable in series significantly improve the quadrature rejection ability of the sensor. The circuits include a synchronous detector, passive and active filters and a decimator.