The latest module in the Erica Synths and Moritz Klein educational DIY modular series is a 3-channel mixer with built-in diode distortion.
EDU DIY Mixer
Module number 6 in the EDU DIY range of modules is an unassuming-looking 3-channel mixer. 3 inputs at the top and 3 outputs at the bottom with 3 small trimmer-style knobs in the middle. That doesn’t sound very exciting. But mixers are vital parts of a modular system that enable us to combine signals and get the full sonic potential out of our oscillators.
However, behind the scenes, a hidden superpower will give the mixer a good bit of character. Delving into the build manual we can see that Moritz has added a diode distortion circuit. It consists of a pair of diodes, four resistors and an op-amp. Very simply as the output rises the diodes start to open and cut off the waveform above a certain threshold causing clipping. As this happens gradually the edges get rounded off producing what we call soft-clipping.
As with all the modules in the series, building the Mixer aims to take you through the circuit design by building it out on a breadboard. As the functionality grows more complex you build more of the circuit on the board. There’s a bit of testing and listening along the way. Once you’ve followed the well-written and fully illustrated manuals you can then solder the kit together into a finished module.
The Mixer then joins the VCO, VCA, Sequencer, VCF and Envelopes in the Erica Synths EDU DIY case and leaves us with 3 more to come. If you would like to get into building these DIY modules then I’ve been live streaming my builds of each module as they come (video below). You may find my experiences useful. I’ll also be live-streaming a build of this module in the next week or two.
The kit costs only €45 ex VAT.