The invention provides robust and non-invasive calibration of an adaptive signal conditioning system having a signal conditioning block in the signal path to a signal conversion system, and a feedback path with a number of feedback components for enabling adaptation, by means of a parameter adaptation block, of the parameters used in the signal conditioning. In order to calibrate the feedback path, a well-defined reference signal is inserted into the feedback path, and an appropriate calibration coefficient is then determined by a coefficient calibrator in response to the received reference signal. The calibration coefficient is provided to a compensator, which effectively compensates for changes in the transfer characteristics of the feedback path due to factors such as variations in ambient temperature and component aging. Accordingly, the feedback signal transferred over the calibrated feedback path will be an accurate representation of the output signal of the signal conversion system, thus allowing accurate adaptive signal conditioning.