In most cases the increase in voice coil temperature is the major cause for speaker failure.Several techniques have been developed to keep voice coil at room temperature under high power inputs.It is a known fact that rise in temperature causes a rise in the total resistance of the voice coil.Providing negative impedance at the amplifier output to compensate for the increase in voice coil resistance is not a new technique.Here we have developed a thermal model to predict the voice coil temperature at different instants of time through computer simulation without actually measuring the voltage across the voice coil and hence calculate the negative impedance required to counteract the increase in voice coil resistance.