Frequency compensated gain control circuit

Claim 1

A BALANCE CONTROL CIRCUIT FOR A DUAL CHANNEL STEREOPHONIC AMPLIFIER ADAPTED TO RECEIVER STEREOPHONICALLY RELATED SIGNALS RESPECTIVELY AT SIGNAL INPUTS OF SAID CHANNELS, COMPISING A PAIR OF POTENTIOMETERS RESPECTIVELY CONNECTED IN EACH OF SAID CHANNELS FOR CONTROLLING THE GAIN THEREOF, EACH OF SAID CHANNELS FOR CONTROLLING THE RESISTANCE ELEMENT PROVIDED WITH A VARIABLE TAP THEREON, MEANS TO APPLY THE SIGNAL OF EACH CHANNEL TO A FIRST END OF THE RESISTANCE ELEMENT OF THE RESPECTIVE POTENTIOMETER IN THE CHANNEL, SIGNAL RETURN MEANS CONNECTED TO THE REMAINING ENDS OF SAID RESISTANCE ELEMENTS, MEANS FOR ADJUSTING SAID VARIABLE TAPS SIMULTANEOUSLY IN OPPOSITE DIRECTIONS OF GAIN CONTROL, THERE BEING A CAPACITANCE BETWEEN EACH OF SAID VARIABLE TAPS AND SAID SIGNAL RETURN MEANS WHICH TENDS TO CAUSE AN UNBALANCED CHANGE IN THE FREQUENCY RESPONSES OF SAID CHANNELS WHEN SAID VARIABLE TAPS ARE ADJUSTED TO ACHIEVE BALANCED GAINS FOR SAID CHANNELS, AND A PAIR OF FREQUENCY COMPENSATION NETWORKS RESPECTIVELY CONNECTED TO EACH OF SAID RESISTANCE ELEMENTS BETWEEN THE FIRST END THEREOF AND A POINT THEREON BETWEEN THE ENDS THEREOF INDEPENDENTLY OF SAID VARIABLE TAP, SAID FREQUENCY COMPENSATION NETWORKS HAVING FREQUENCY CHARACTERISTICS TO COMPENSATE FOR SAID UNBALANCED CHANGE IN FREQUENCY RESPONSES IN SAID CHANNELS THEREBY PROVIDING SUBSTANTIALLY IDENTICAL FREQUENCY RESPONSES FOR SAID CHANNELS FOR ALL SETTINGS OF SAID BALANCE CONTROL.