audio - Schematic to wiring diagram check for 3 mic mixer circuit using TL081 - Electrical Engineering Stack Exchange
Ken Stone's Modular Synthesizer
NYD Passive Summing Box - DIYRE Wiki
XPSum: A new product combining the XPatch with a Analog Summing Mixer — CB Electronics | Specialists in Studio Monitor Controllers, Timecode, Biphase, Serial Control and Remote Control
Simple Stereo Summing Mixer
API500 / PASSIVE SUMMING MIXER – I N E V I T A B L E C R A F T S L A B
AUDIO MIXER under Repository-circuits -53793- : Next.gr