This active tone control circuit will provide about 3db cut and gain for bass and treble. The input can be any source of around 500mV which is roughly the standard low-level signal voltage. This can be used in conjunction with a power amplifier such as 20 bridged amplifier which will provide a cheap but effective amplifier system.
The supply current is about 1.5mA so can be operated as a stand alone unit from a PP3 battery and still give long battery life.

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