Patent ID: 6163613
Filing Date: 2000-12-19
Classification: H04R

Abstract:
A system to minimize the audible effects of voice coil heating and consequent resistance change, inductance and interaction between voice coil and central pole piece in an electro-dynamic loudspeaker, including a magnetic circuit, designed to provide reproduced sound when driven by an audio amplifier comprising:resistor means wired in series with the voice coil of said electrodynamic loudspeaker said resistor means being thermally independent of the voice coil such that heat generated in the series resistor does not appreciably increase the temperature of the voice coil in such degree as to affect the voice coil's resistance; and wherein the resistive sum of the resistor means and the voice coil impedance during operation is substantially equal to the operating impedance of the speaker and the operating impedance is substantially constant during all conditions of operation.