Comparing the order of a polynomial phase model for the synthesis of quasi-harmonic audio signals

Sinusoidal modeling has been successfully applied to a wide range of audio signal processing problems, such as coding or time and frequency stretching. While many methods have been proposed for the analysis part of the process, it seems that there is some general agreement concerning the synthesis part in the nonoverlapping case: It is very often achieved by using the well-known McAulay-Quatieri method, which consists of an order 3 polynomial reconstruction of the phases of the sinusoidal model partials. We compare this "classical" approach with both a simpler (order 1, that is, linear interpolation) and a more complex (order 5) polynomial model for phase interpolation of quasi-harmonic signals. A gain has been measured in the signal-to-noise ratio at the synthesis stage, although the performance is limited by the amplitude model and by the imprecision in the analysis stage.