At a glance Audio Processor circuit scheme is similar to Tone Control. Advantages of Audio Processor is to provide reinforcement effect tone Bass (Bottom), Middle (Phase and Body) and Treble (Edge) are more pronounced than the Tone Control Regular, In addition, this circuit provides control functions "Clip" which provides that if setting is too big / Over. please try this circuit and distinguished from other similar circuits.
Audio Processor Circuit using IC LM324 , 4x IC for tone controller. By using assymetric power supply or ct power supply circuit 12V - 15V DC you can operate this audio processor circuit see schematic below.