I forget where I read it, but that's the design behind the OP-1 by teenage engineering. https://www.teenageengineering.com/products/op-1 https://www.teenageengi

I forget where I read it, but that's the design behind the OP-1 by teenage engineering. https://www.teenageengineering.com/products/op-1 https://www.teenageengineering.com/products/op-1