Adaptive compensation of temperature fluctuation effect in sound reproduction system

We describe a method of compensating temperature fluctuation effect by linear-time-warping processing in a sound reproduction system. This technique is applied to impulse responses of room transfer functions, to achieve a high-quality sound reproduction system, particularly one that treats high-frequency components. The impulse responses are measured before and after temperature fluctuation, and the former are converted to the latter by the proposed process. We design inverse filters for the system, and evaluate the improvement of the reproduction accuracy and spectrum distortion. Also, we propose a adaptive algorithm for the warping ratio estimation, using the observed signal of reproduced sound which is obtained at only one control point, and we can determine a suitable warping ratio which improves the reproduction accuracy at every control point by about 14 dB.