A noise cancelling system is described for a in a patient implantable hearing implant system. An implantable microphone senses a sound signal present at the microphone that includes a sound source component from a sound source external to the patient, and a noise component from internal bone conduction. At least one implantable noise sensing element is located near the microphone to sense the noise component. A filter is controlled by an adaptive algorithm responsive to transform the noise component and outputs a transducer control signal. A bone conduction transducer receives the transducer control signal and generates a corresponding mechanical vibration signal to the skull bone. The adaptive algorithm controls the filter so that the mechanical vibration signal of the bone conduction transducer offsets the noise component sensed by the at least one noise sensing element so as to minimize the noise component sensed by the implantable microphone.