About

This module is a dual voltage adder: each half takes in 5 signals, and on the output you get a mixture of those signals. The amplitude, or volume, of the signals can be controlled with the knobs. The module can be built in a way so the knobs act as attenuators, or attenueverters (attenuator-inverters). update 20 march 2021: BULLSHIT! The schematic i made back then only works for unipolar mode. It cannot be attenuverter-ized! I made a new, normal schematic now. If you want something that can be attenuators or attenuverters, better check this out! Each input of the second adder has the corresponding input of the first adder normalized to it, so by putting a signal into adder A's in, you automatically get on adder B's input next to it: on the paperface, i denoted it with arrows. This makes the unit a nice stereo mixer, or a matrix CV summator. Of course you can also use it as two separate voltage processors.

Schematic

This device is very very simple. You can visit Doepfer's DIY guide page - worth to pay a visit for a novice DIYer! This is basically Matrix Mixer, but every matrix column has its own inputs with inputs of previous one normalized to it, and, well, there are just two columns. The old schematic had 2 buffer options for polarized and unpolarized mixing, and it was totally, absolutely wrong. No wonder it worked weirdly. I'm sorry if someone had to go through the hell of trying to build it! This, new schematic, is correct, though, and it can only be unpolarized. For polarized summation, take a look at my new (and way better made) unit, the Dual Utility Summator.

Pictures