his stereo tone control module is designed for use in audio equipment. It allows smooth adjustment of the frequency response of the audio signal by boosting or attenuating low, mid, and high frequencies.
The unit should be connected between the preamplifier and the power amplifier stage. Adjustment is carried out with three dual potentiometers (RV1–RV3):
RV1 – bass (low frequencies)
RV2 – treble (high frequencies)
RV3 – midrange (mid frequencies)
The circuit uses low-noise operational amplifiers with a low distortion factor as active elements. The U2A stage generates a stabilized virtual ground, enabling operation with a single-polarity power supply.
Supply voltage: 6–20 V
Input voltage: 0.1–0.2 V
Output voltage: up to 0.5 V
Current consumption: 15 mA
First, solder the wire jumpers located:
• between RV1, RV3 and C2, C4 – 2 pcs
• between R6 and R18 – 2 pcs
• near R24 – 2 pcs
Some resistors must be mounted vertically.
Power supply, signal source, and output load should be connected with wires according to the component placement diagram.