kind of a utility PCB, no pots, just jacks.
Moog fixed filters - brass, vibes, humana, funk, harpsichord
another fixed parallel BP voice filter (called gargle)
These can of course be used with any audio or noise source but are intended primarily as filters for the extra outputs on the Veena.
Also has white noise, pink noise, random vibrato, slow random, chunder (roar)
2X difference rectifiers
4046 phase locked loop circuit

difference rectifier

this circuit is very simple, just one op amp stage, but when fed 2-4 CV signals it produces a wonderful array of complex envelopes. In the vid, the blue and yellow traces are the inputs, the pink one is the output. It starts off fast but slows down after a minute, so it is easier to see what the cct is doing.