Heterodyne Space Explorer

A classic Beavis Audio Research CMOS synth, this flexible tone generator is comprised of four 40106 square wave oscillators.

The supply voltage can be sagged to create starved sounds as each oscillator competes for voltage. Each output stage goes to a switch that flips between a resistor mixer and a diode mixer. Each sounds different.

Each stage also has its own volume knob, making it easy to create beating heterodyning noise walls.

You’ll find the schematic here.