This audio amplifier is simple, small and easy to build. This mini amplifier can be a universal audio amplifier. It is built with an 741 IC, 2 transistors 2N1711 (2N1613, 2N3901, 2N3110) and 2N2904 (2N2905). With P1 you adjust the volume level and P2 controls the tone and can suppress high frequencies up to 20 dB. The output power in around 2 watts, input sensitivity is 100mV and at a power supply of 16V to 24V the current consumption is around 150mA. continue reading…