In 1983, Korg released the Poly-800, their reply to Roland's Juno-106. The Poly-800 was based on an arcade chip (MSM5232) and used a master clock divide-down system similar to drawbar organs and the Korg Delta before it. The synth adds together square waves to create an approximation to sawtooth waves, similar to how we can create a square wave by adding together sine waves.
This simple technique makes a great starting point for your own DIY synth. At this demo you can explore how to build such a system whether with analogue parts, Arduinos, or in PureData. Or just come and play on a recreation of the Poly 800.
