Schematic diagram of the Active Tone Control circuit

Below is the schematic diagram of the Active Tone Control circuit or we often call this circuit as "ACTOR". This circuit is very simple, easy to build and cheap, you can build this circuit with minimal/low cost.

Active Tone Control or ACTOR is an active electronic audio circuit used to increase the loudness (bass and treble audio signals) as it uses the Baxandall system. This circuit does not use potentiometers so it cannot control the output audio signal. S1 acts as an option if the circuit is enabled or disabled (bypassed).

The circuit is powered by a 12V DC supply. The above circuit is once mono, for stereo applications you need two identical circuits, connect the supplies in parallel, and use a DPDT switch.