Here is the circuit diagram of an excellent stereo preamplifier with tone control using the IC TDA1524 from Phillips. The IC requires very few external components, has very low noise and has a wide power supply voltage range. POTs R1 to R4 can be used for controlling the volume, balance, bass and treble respectively. LED is D1 is a power ON indicator and R1o is its current limiting resistor.
- Assemble the circuit on a good quality PCB.
- Switch S2 is the ON/OFF switch.
- Swich S1 can be used to select linear or contour mode.
- Supply voltage can be anything between 8 to 16V .Here I used 12V DC.