Microphone Mixer

By  Ajomon sebastian

This relatively simple mixer was designed for three dynamic microphones, but can be re-designed for more or less. Level and tone controls are available to tailor the sound to your needs.

Schematic

Schematic for mixer

Parts:

Part
Total Qty.
Description
Substitutions
R1, R2, R3 3 1K 1/4W Resistor
R4, R5, R6 3 10K Logarithmic Pot
R7 1 1Meg 1/4W Resistor
R8, R10 2 10K 1/4W Resistor
R9, R11 2 100K Linear Pot
C1, C2, C5, C6 4 0.1uF Ceramic Disc Capacitor
C3, C4 2 22nF Ceramic Disc Capacitor
U1, U2 2 741 Op Amp
J1, J2, J3 3 Input Jacks Of Your Choice
MISC 1 Board, Wire, Knobs, IC Sockets

Notes:

1. Email Ajomon Sebastian with questions, comments, etc.

2. R1-R3 are level controls. R9 and R11 control bass and treble, respectively.

3. Since the circuit draws such low current, two 9V batteries can be used for a power supply.

4. Building the mixer in a metal case will cut down on noise.