A method of determining when to save default coefficients in an echo
canceller so as to ensure that the capture of coefficients that
correspond to the best possible echo cancellation in a current condition.
Coefficients are saved at varying times depending on the amount of echo
removed by the echo canceller. More particularly, the present method
involves constantly monitoring the error signal to the echo canceller and
comparing it with the error signal that would be obtained if default
coefficients were to be used instead of the current coefficients. This
ensures that the default coefficients are upgraded each time the current
set of coefficients is better than the saved default coefficients.