Mini 4 Channel Audio Mixer

A very simple active audio mixer with 4 3.5mm inputs, and 1 3.5mm output. USB-powered. The default gain is 1:1 on all channels, although this can be changed by altering resistor values and/or installing potentiometers. I built this as a simple way to run multiple sources into a set of computer speakers. It is designed to fit in a commonly-available 90x70x28mm enclosure with end panels that can be either laser-cut or made from PCBs.

This project uses symbols from https://github.com/ArrestedLightning/al_kicad_libraries/. It is licensed CC BY 4.0.