Since I have a multi channel Bheringer mixer which I use to mix the modular output and some synths with I thought I would not have much to contribute to this thread, but maybe this could be of interest. In my modular I use ‘intermediate’ mixers (called Mix-O-Matic) which are signal and/or CV mixers. These are very simple in construction and easy to use. I’ve been using them for a while now and like multiples and attenuverters they are sort of a staple tool to me now. They consist of TL072s (but I could have used one TL074) which are configured as an inverting summing amplifier followed by an inverter each. This results in 2 summing circuits. For one I also output the inverse sum.
Here is a look at two bread board implementations.
