The LM1036 is a DC controlled tone (bass/treble), volume and balance circuit which can be applied in car radio, TV and audio systems. Loudness compensation to be simply effected is allowed by an additional control input.
Control of the bass, treble, balance and volume function are provided by four control inputs through application of DC voltages from remote control system or, alternatively, from four potentiometer which may be biased from a zener regulated supply provided on the circuit. To give the desired characteristic, each tone response is defined by a single capacitor chosen. [Source: National Semiconductor Application Note]