Abstract: There is disclosed a motor speed control circuit for use in battery-powered tape recorders, tape players and record players in which the motor speed is made independent of power supply voltage swings, temperature and loading. The circuit is comprised of three sections including a discriminator-comparator section, a protection circuit and an output circuit. The discriminator-comparator circuit provides that the control signal to the motor be independent of power supply variations. A tachometer signal of an AC nature is coupled into the discriminator-comparator circuit which generates a pulsed current. The number of current pulses generated over a given time interval corresponds to the frequency of the tachometer signal. These pulses are subtracted from a reference current which difference is integrated, with the integrated current difference indicating the difference in speed of the motor between the desired speed and the actual speed.