I do not think the Procyon can synthesise a sine modulated carrier signal.
I know it is my quote, but if the SessionEditor's dropdown box is set to a colour, then the audio signal is modulated by it.
If the dropdown box is set to none, then binarual beats are used.
The example is not exactly clear, and shows the BB frequency of 5HZ, though the LEDs are flashing at 10. And there seems no automatic way to get the BB frequency to follow the visual frequency.
This might be wrong, i've not tried the machine yet, but would've hoped that it would be easier than this (to create synchronised visual - BB signals).