A model-based method for assessing acoustic signal quality in a heart monitoring device. The personal heart sound interval distribution of a person being actively monitored is compared with a modeled global heart sound interval distribution shared by most human beings after which processing action is taken consistent with the quality assessment. The error in the best fit between the personal interval distribution and the global interval distribution is presumed to be caused predominantly by noise, allowing the quality of the fit to serve as a proxy for the level of noise in the acoustic signal and used in making processing decisions.
