Adaptive active sound quality control algorithm

This paper presents an adaptive active sound-quality control (ASQC) system using the active noise equalization (ANE), the filtered-error least-mean-square (FELMS) algorithm, and the normalized reference signal generator. The integrated ASQC algorithm achieves desired spectral shaping of residual noise for controlling the sound quality. This optimized ASQC system uses the FELMS algorithm to limit high gains in passband, thereby increasing the system stability. Fast convergence is achieved by normalizing amplitudes of sinusoidal components in the reference signal according to the magnitude responses of secondary path at the corresponding frequencies. Computer simulations show faster convergence and reduced passband disturbance as compared to the original ANE system.