The phase-sensitive rectification method (lock-in technique) is presented and tested to serve as another evaluation method for temperature-modulated differential scanning calorimetric measurements. This is done by model calculations with a mathematical computation system, using simple models of events often measured in this type of calorimeter : changes in heat capacity, cold crystallization, a chemical reaction anti the glass transition. The advantages of the new evaluation method are : a lower numerical expenditure; a well-defined connection between time resolution and smoothing interval; and a reliable decrease in fluctuations of the results. It has furthermore been demonstrated that numerical calculations can be a powerful tool to test different models and their influence on the measured signal and the evaluated results. This is especially significant in cases, where a certain process produces non-linear distortions of the heat-flow rate signal.