Computation of common acoustical poles in subbands by means of a clustering technique

This paper presents a new and simple method for calculating the common poles of a room. A set of impulse responses is measured inside a room. ARMA models are computed for each of these measured impulse responses. Since the measured linear systems are stable, the poles of the ARMA models are located inside the unit circle of the Z plane. A clustering technique can be used to group these points into clusters. The centroids of these clusters can be interpreted as the common poles of the room. The analysis was carried out in a subband basis considering only the poles inside the pass-band of the bandpass filter. The clustering technique shows a considerable improvement compared to the averaging method proposed by Haneda et al., and the stability of the new common acoustical poles models can be theoretically assured.