Microphone mixeris used for the 3 microphone and made use IC . is used for mixer is working on a class AB has a high gain factor and a very low current consumption. Audio mixer can be supplied with DC voltage ± 12 Volt symmetrical up to ± 15 Volts. The series of three channel mixer is designed specifically for the use of dynamic microphone with volume control located on each of the microphone channels.
3 channelmixer circuit above is made by IC is set as a non-inverting . The amount of signal amplification by audio from a microphone pre amp on the above formulated by (1 + (100K/1K)) so that the gain factor of the circuit above is an 101 with a signal level at the mixer can be adjusted by a potentiometer on each chanelnya. Function R5, R6 and R7 on the audio mixer channel 3 above to adjust the output signal level from the mic pre amps on each channel.