A CONSIDERATION OF THE ELIMINATION OF NONLINEAR DISTORTION OF A LOUDSPEAKER SYSTEM BY USING A DIGITAL VOLTERRA FILTER

The distortion of a speaker system at the end of an audio playback sys tem can be divided into linear distortion and nonlinear distortion. Th e authors have carried out research on elimination of linear distortio n by using digital filters. In this process, when the equalization eff ect at low frequencies is increased, the amplitude of the speaker vibr ating plate increases so that the nonlinear distortion increases. Ther efore, in order to construct a high fidelity audio playback system wit hout distortion, it is necessary to eliminate nonlinear distortion in addition to linear distortion. To this end, a Volterra series that des cribes the nonlinear input-output relationship is used to identify the audio playback system. A procedure for the design of an inverse syste m is proposed. In addition, a simulation is carried out. It was found possible to reduce the nonlinear distortion of a speaker system by as much as 100 dB by using the proposed method. (C) 1998 Scripta Technica .