The Duoctawave monitors two of 8 inputs at a time.

One monitored input is lit by a Red RGB Light node, while the other is lit by a Blue RGB Light node.  If both are monitoring the same signal, you will see only one Purple RGB Light node.

The button marked R in the upper right cycles the Red light through inputs, while the button marked B does the same for the Blue light.

The Knob above the button sets the maximum number of inputs – useful if you only want to cycle between a few inputs.  Disabled inputs are unlit.

Waves above +1 and below -1 will not render correctly.