Causal/anticausal Decomposition for mixed-phase Description of brass and Bowed String sounds

In this paper we present a new method for the decomposition of musical sounds into causal and anticausal contributions. The algorithm is based on a particular separation of zeros of the Z-Transform (ZZT) of signal frames, currently used in speech processing for glottal source parameters estimation. Acoustics of two particular continuous interaction instruments (CII) – trumpet and violin – is discussed and the use of a mixed-phase model for synthesis is proposed. First results are presented and relevance of extracted causal and anticausal contributions is evaluated.