2010 Volume 31 Issue 5 Pages 337-346
In this paper, we propose a sound field creation system based on the simultaneous equations method used for active noise control systems. Conventional studies on such sound field creation mainly focus on the transaural system reproducing recorded signals at the listening points. We differently purpose a system that creates the same sound field as that of a target. In the proposed system, inverse filters forming the target sound field are derived by using the simultaneous equations method, which is characterized by the use of auxiliary filters in estimating the error between the created and the target sounds. The auxiliary filters can also be used for detecting the deficiency in the number of taps of the inverse filters and in the delays to be added to the target sound field. The latter not only increases the error but also generates echoes preceding the created sound, which is annoying to listeners. In this paper, we finally verify the performance of the proposed system and also that the insufficiency can be detected by monitoring the coefficients of the auxiliary filter, by computer simulations.
