When I was a teenager and getting interested in hobby electronics, I really wanted to build a modular synthesizer. There were plenty of electronics magazines offering projects to build them, but on my very low income, they were beyond my reach.

Now, many, many years later, I have a decent income, have paid off my mortgage, and have a small amount of free time to tinker with electronics, so I have rekindled my desire to build a modular synthesizer, which I shall be writing about on here. I might even get into making videos about it to put on my YouTube channel. If that ever comes about, I’ll be embedding the videos here, too.

Note, the image here is a monstrosity created by one of those so-called AI tools. It doesn’t understand the layout of a music keyboard. My synth is not going to look anything like that.

Getting Started

My plan is to build as much as possible from scratch. Ready made modules and kits can be very expensive, and part of the enjoyment for me is to design and build the parts myself.

Fundamentals

Many people wanting to get started on such a project tend to jump in and build VCOs and VCAs etc., and end up with a mass of wires all over the place. It’s great to have that enthusiasm, but things will go a lot more smoothly if you get the boring (less interesting at least!) parts out of the way.

To this end, I am starting with a case/rack and a power supply unit (PSU). Once they are constructed and fixed up, I will have a nice convenient place to mount and test my modules as I build them.

Format

There are a few formats of modular synthesis modules. Their face plate dimensions vary, as do the power requirements and even the size of the jack sockets used to interconnect the modules.

I am going to use the Kosmo format made popular by Look Mum No Computer. The front panels are 200 mm high and use 1/4″ jack sockets.

What’s in a name?

As I am using the Kosmo format, I thought I’d incorporate that into the name of my synth, so my mind drifted to Cosmonaut (Russian for Astronaut). I’m a professional software engineer, and we frequently use zero to mean the first of something, so Cosmonaut has evolved into KosmoNought – my first Kosmo synthesizer.