Active Summing Mixer Schematic. The linear mixer is a summing amplifier which is used widely in audio and other applications to sum signals. The audio mixing circuit alone is a very simple summing amplifier.
Vo a1 v1 a2 v2 a3 v3 an vn ax is the voltage gain for the xth input and it is equal to rf rx. The inputs of the summing amplifier circuit are qa qb qc and qd. Each signal is summed in a totally linear fashion.
Vo a1 v1 a2 v2 a3 v3 an vn ax is the voltage gain for the xth input and it is equal to rf rx.
Building a passive summing box always seemed like a bit more of a hassle than it should be for such a simple circuit until i found rhythm in mind s idea for mounting everything on a front panel. The mic inputs are suitable for low impedance 200 1000r dynamic microphones. If the inputs resistors r 1 r 2 r 3 etc are all equal a unity gain inverting adder will be made. Simply drill a panel as i ve drawn below.
