Importance

Loading Importance Indicators...

Abstract

A motional feedback loudspeaker system provides acceptable bass performance even with inexpensive speakers by the reduction of nonlinear distortion with the use of feedback derived from the back emf signal generated by the motion of the voice-coil within the magnet field. A novel linearizing circuit corrects the nonlinearity of the back emf signal due to the falloff of the BL factor as a function of cone displacement. The linearizing circuit is a recursive feedback loop comprising a multiplier for multiplying the back emf signal by a corrective function which is the inverse of the BL nonlinearity so as to provide a velocity signal linearly proportional to the cone velocity, an integrator for integrating the velocity signal to generate a displacement signal linearly proportional to the cone displacement, and a correction generator comprising a nonlinear curve shaper responsive to the displacement signal to generate said corrective function.

Loading the Abstract Image...

First Claim