The original version of this circuit was obtained in a 1995 magazine Electronics Now. The magazine no longer exists, but we made some changes in the circuit in order to make a viable assembly today. What we have is the implementation of an active tone control using a integrated circuit 741. The circuit controls bass and treble and uses symmetric power supply of 15 V. The source must have excellent filtration. Two circuits like this should be mounted for stereo operation. Input cables and output must be shielded. Equivalent operational amplifiers can be used. Pots should be linear. The circuit does not include the volume control that should be in the power amplifier.
