831 project page – Revised 02/09/02
The 831 is a 3-IN, 3-OUT voltage interval switcher that does not have separate octave and step switches. Instead the intervals (5 up and 5 down) are selectable by the user at the time of construction. It can be used to instantly select musically useful intervals instead of trying to manually tune them each time.
The 831 schematic has been revised. VR11, VR11, R27, and R38 are tweaked. This is not a required update. 
Notice
Since the 831 PCB is officially sold out, and will no longer be produced, I plan to eventually remove the 831 documentation from this web site. I encourage you to download what you wish to have permanently. I will keep this information posted until about 05/01/2002.